Relay "clicking" periodically when ignition is off | Electronics Forum (Circuits, Projects and Microcontrollers)

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Registration is free. <a href="/register">Click here to register now</a>. </div> </li> </ul> <center><div id='div-gpt-eto-header'> <script> googletag.cmd.push(function() { googletag.display('div-gpt-eto-header'); }); </script> </div></center> <div class="p-breadcrumbs--parent "> <ul class="p-breadcrumbs " itemscope itemtype="https://schema.org/BreadcrumbList"> <li itemprop="itemListElement" itemscope itemtype="https://schema.org/ListItem"> <a href="/#electronics-categories.21" itemprop="item"> <span itemprop="name">Electronics Categories</span> </a> <meta itemprop="position" content="1" /> </li> <li itemprop="itemListElement" itemscope itemtype="https://schema.org/ListItem"> <a href="/forums/automotive-electronics/" itemprop="item"> <span itemprop="name">Automotive Electronics</span> </a> <meta itemprop="position" content="2" /> </li> </ul> </div> <noscript class="js-jsWarning"><div class="blockMessage blockMessage--important blockMessage--iconic u-noJsOnly">JavaScript is disabled. 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It may not display this or other websites correctly.<br />You should upgrade or use an <a href="https://www.google.com/chrome/" target="_blank" rel="noopener">alternative browser</a>.</div> <div class="p-body-header"> <div class="p-title "> <h1 class="p-title-value">Relay "clicking" periodically when ignition is off</h1> </div> <div class="p-description"> <ul class="listInline listInline--bullet"> <li> <i class="fa--xf fal fa-user" aria-hidden="true" title="Thread starter"></i> <span class="u-srOnly">Thread starter</span> <a href="/members/xiaohao76.326639/" class="username u-concealed" dir="auto" data-user-id="326639" data-xf-init="member-tooltip">xiaohao76</a> </li> <li> <i class="fa--xf fal fa-clock" aria-hidden="true" title="Start date"></i> <span class="u-srOnly">Start date</span> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/" class="u-concealed"><time class="u-dt" dir="auto" datetime="2024-08-08T09:01:15-0700" data-time="1723132875" data-date-string="Aug 8, 2024" data-time-string="9:01 AM" title="Aug 8, 2024 at 9:01 AM">Aug 8, 2024</time></a> </li> </ul> </div> </div> <div class="p-body-main p-body-main--withSidebar "> <div class="p-body-contentCol"></div> <div class="p-body-sidebarCol"></div> <div class="p-body-content"> <div class="p-body-pageContent"> <div class="block block--messages " data-xf-init="lightbox select-to-quote" data-message-selector=".js-post" data-lb-id="thread-166396"> <div class="block-outer"></div> <div class="block-outer js-threadStatusField"></div> <div class="block-container"> <div class="block-body"> <article class="message message--post js-post js-inlineModContainer " data-author="xiaohao76" data-content="post-1454111" id="js-post-1454111" > <span class="u-anchorTarget" id="post-1454111"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" > <div class="message-avatar "> <div class="message-avatar-wrapper"> <a href="/members/xiaohao76.326639/" class="avatar avatar--m avatar--default avatar--default--dynamic" data-user-id="326639" data-xf-init="member-tooltip" style="background-color: #d6b85c; color: #66531a"> <span class="avatar-u326639-m" role="img" aria-label="xiaohao76">X</span> </a> </div> </div> <div class="message-userDetails"> <h4 class="message-name"><a href="/members/xiaohao76.326639/" class="username " dir="auto" data-user-id="326639" data-xf-init="member-tooltip">xiaohao76</a></h4> <h5 class="userTitle message-userTitle" dir="auto">New Member</h5> </div> <span class="message-userArrow"></span> </section> </div> <div class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454111" rel="nofollow" > <time class="u-dt" dir="auto" datetime="2024-08-08T09:01:15-0700" data-time="1723132875" data-date-string="Aug 8, 2024" data-time-string="9:01 AM" title="Aug 8, 2024 at 9:01 AM">Aug 8, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454111" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454111/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454111" rel="nofollow"> #1 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454111" data-lb-caption-desc="xiaohao76 · Aug 8, 2024 at 9:01 AM"> <article class="message-body js-selectToQuote"> <div > <div class="bbWrapper">Hello guys,<br /> <br /> I'm facing a weird issue with my Kia Cerato.<br /> <br /> I purchased this car a few months back from the secondhand market. While resting in my car with the ignition off, I noticed there's a knocking sound coming from the back off my car periodically. Initially, I ignored the sound and didn't think much about it. It was until I faced a problem where I was unable to start the car when the car was not driven for ~3 days, as the battery level was low and needed a jumpstart.<br /> <br /> I started looking deeper into what could be draining the car battery within a few days (the battery is new). Unplugging the car cam did not help and I had to jumpstart the car on a second occasion.<br /> <br /> Then I remember the knocking sound which I was hearing periodically with the engine off and suspected that could be the cause of battery drain. The knocking sound could be heard every 13 seconds. Guessing the sound was coming from the fuel pump, I opened up the fuse box. And true enough, the fuel pump relay could be heard clicking every 13 seconds. I unplugged the fuel pump relay, and the knocking stopped.<br /> <br /> With the fuel pump relay unplugged, now I could hear another sound coming from around the engine (again every 13 seconds). So this time, I unplugged the main relay and the sound stopped.<br /> <br /> So it seems like every 13 seconds, there is something powering up the main relay, which is also powering up the fuel pump relay and a few other components and it's draining the battery.<br /> <br /> Would anyone be able to advise what could be the problem? Is this normal?</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> </div> </article> </div> </div> </div> <div class="block block--messages" data-xf-init="" data-type="post" data-href="/inline-mod/" data-search-target="*"> <span class="u-anchorTarget" id="posts"></span> <div class="block-outer"><div class="block-outer-opposite"> <div class="tabs tabs--standalone tabs--standalone--small tabs--standalone--inline"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/" class="tabs-tab is-active" rel="nofollow"> Sort by date </a> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/?order=vote_score" class="tabs-tab " rel="nofollow"> Sort by votes </a> </div> </div></div> <div class="block-container lbContainer" 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href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454114" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-08T11:01:29-0700" data-time="1723140089" data-date-string="Aug 8, 2024" data-time-string="11:01 AM" title="Aug 8, 2024 at 11:01 AM" itemprop="datePublished">Aug 8, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454114" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454114/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454114" rel="nofollow"> #2 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454114" data-lb-caption-desc="aliarifat794 · Aug 8, 2024 at 11:01 AM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper">It can be due to a short circuit or a faulty relay itself.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454114"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score js-voteCount" data-score="0">0</span> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--down " data-vote="down"><span class="u-srOnly">Downvote</span></a> </div> </div> </div> </div> </article> <article class="message message--post js-post js-inlineModContainer " data-author="rjenkinsgb" data-content="post-1454123" id="js-post-1454123" itemscope itemtype="https://schema.org/Answer" itemid="https://www.electro-tech-online.com/posts/1454123/"> <meta itemprop="parentItem" itemscope itemid="https://www.electro-tech-online.com/threads/relay-clicking-periodically-when-ignition-is-off.166396/" /> <span class="u-anchorTarget" id="post-1454123"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" itemprop="author" itemscope 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message-userBanner" itemprop="jobTitle"><span class="userBanner-before"></span><strong>Most Helpful Member</strong><span class="userBanner-after"></span></div> </div> <span class="message-userArrow"></span> </section> </div> <div class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454123" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-08T23:04:59-0700" data-time="1723183499" data-date-string="Aug 8, 2024" data-time-string="11:04 PM" title="Aug 8, 2024 at 11:04 PM" itemprop="datePublished">Aug 8, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454123" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454123/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454123" rel="nofollow"> #3 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454123" data-lb-caption-desc="rjenkinsgb · Aug 8, 2024 at 11:04 PM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper">My initial guess would be a corroded connectors somewhere with leakage between the pins.<br /> Or, that a module on one of the data bus circuits is not shutting down properly - which could have the same cause, or it could be a faulty module.<br /> <br /> Check all the fuses are OK to start with.<br /> <br /> One test method for modules not shutting down is to use a multimeter on the millivolts range and measure across the testpoints in the top of each fuse. It will be non zero on any fuses that are passing current - then look what that fuse relates to in the fuse chart.<br /> <br /> Do that with the two relays out, so you are not reading the current they take.<br /> <br /> <br /> Also check for any sign of water ingress anywhere, under the carpets or below the boot lining. If there is any trace it has been damp, look for any connectors that may have been affected in those areas - clean and dry them thoroughly, then treat the contacts with deoxit and the outside with WD40.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454123"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" 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href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454131" rel="nofollow"> #4 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454131" data-lb-caption-desc="Terry_g · Aug 9, 2024 at 5:03 AM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper">Take the vehicle to someone that has the ability to scan it. <br /> Something might show up and save a lot of troubleshooting time.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList is-active"> <ul class="reactionSummary"> 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class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454132" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-09T05:48:28-0700" data-time="1723207708" data-date-string="Aug 9, 2024" data-time-string="5:48 AM" title="Aug 9, 2024 at 5:48 AM" itemprop="datePublished">Aug 9, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454132" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454132/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454132" rel="nofollow"> #5 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454132" data-lb-caption-desc="danadak · Aug 9, 2024 at 5:48 AM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper">Usually, not always, there is a mode vehicle can be put in to dump codes<br /> via dash indicators. Sometimes involving using a jumper in a fuse block<br /> or scan block connector. Google you vehicle model and "codes" to see if you<br /> can get a hit, or go to that manufacturers forums to see if anyone else<br /> has discussed code dumps.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList is-active"> <ul class="reactionSummary"> <li><span class="reaction reaction--small reaction--1" data-reaction-id="1"><i aria-hidden="true"></i><img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="reaction-sprite js-reaction" alt="Like" title="Like" /></span></li> </ul> <span class="u-srOnly">Reactions:</span> <a class="reactionsBar-link" href="/posts/1454132/reactions" data-xf-click="overlay" data-cache="false" rel="nofollow"><bdi>xiaohao76</bdi></a> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454132"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score js-voteCount" data-score="0">0</span> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--down " data-vote="down"><span class="u-srOnly">Downvote</span></a> </div> </div> </div> </div> </article> <article class="message message--post js-post js-inlineModContainer " data-author="xiaohao76" data-content="post-1454133" id="js-post-1454133" itemscope itemtype="https://schema.org/Answer" itemid="https://www.electro-tech-online.com/posts/1454133/"> <meta itemprop="parentItem" itemscope itemid="https://www.electro-tech-online.com/threads/relay-clicking-periodically-when-ignition-is-off.166396/" /> <span class="u-anchorTarget" id="post-1454133"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" itemprop="author" itemscope itemtype="https://schema.org/Person" itemid="https://www.electro-tech-online.com/members/xiaohao76.326639/"> <meta itemprop="url" content="https://www.electro-tech-online.com/members/xiaohao76.326639/" /> <div class="message-avatar "> <div class="message-avatar-wrapper"> <a href="/members/xiaohao76.326639/" class="avatar avatar--m avatar--default avatar--default--dynamic" data-user-id="326639" data-xf-init="member-tooltip" style="background-color: #d6b85c; color: #66531a"> <span class="avatar-u326639-m" role="img" aria-label="xiaohao76">X</span> </a> </div> </div> <div class="message-userDetails"> <h4 class="message-name"><a href="/members/xiaohao76.326639/" class="username " dir="auto" data-user-id="326639" data-xf-init="member-tooltip"><span itemprop="name">xiaohao76</span></a></h4> <h5 class="userTitle message-userTitle" dir="auto" itemprop="jobTitle">New Member</h5> </div> <span class="message-userArrow"></span> </section> </div> <div class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454133" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-09T09:11:29-0700" data-time="1723219889" data-date-string="Aug 9, 2024" data-time-string="9:11 AM" title="Aug 9, 2024 at 9:11 AM" itemprop="datePublished">Aug 9, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454133" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454133/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454133" rel="nofollow"> #6 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454133" data-lb-caption-desc="xiaohao76 · Aug 9, 2024 at 9:11 AM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper"><blockquote data-attributes="member: 325293" data-quote="aliarifat794" data-source="post: 1454114" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-title"> <a href="/goto/post?id=1454114" class="bbCodeBlock-sourceJump" rel="nofollow" data-xf-click="attribution" data-content-selector="#post-1454114">aliarifat794 said:</a> </div> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> It can be due to a short circuit or a faulty relay itself. </div> <div class="bbCodeBlock-expandLink js-expandLink"><a role="button" tabindex="0">Click to expand...</a></div> </div> </blockquote>I've replaced the main relay, but the issue still persist. And I don't think there is any issue with the fuel pump relay, else it wouldn't be clicking.<br /> <br /> I troubleshoot today by pulling the fuse out one by one. I noticed the following:<br /> - Pulling out ECU 1 fuse, both main and fuel pump relay stopped. and when it was plugged back in, no further clicking was heard. But issue will re-surface once the ignition is turned on and off again.<br /> - Pulling out SNSR 2 fuse, the fuel pump relay stopped clicking. I checked the owner's manual, SNSR 2 fuse is for the following: Oil Control Valve (#1, #2), Camshaft Position Sensor (Intake, Exhaust), F/PUMP Relay,C/FAN LO Relay, Immobilizer Module<br /> - Pulling out the fuel pump fuse, it was surprising to me that the fuel pump relay did not stop clicking.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> <div class="message-lastEdit"> Last edited: <time class="u-dt" dir="auto" datetime="2024-08-09T10:44:49-0700" data-time="1723225489" data-date-string="Aug 9, 2024" data-time-string="10:44 AM" title="Aug 9, 2024 at 10:44 AM" itemprop="dateModified">Aug 9, 2024</time> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454133"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score js-voteCount" data-score="0">0</span> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--down " data-vote="down"><span class="u-srOnly">Downvote</span></a> </div> </div> </div> </div> </article> <article class="message message--post js-post js-inlineModContainer " data-author="xiaohao76" data-content="post-1454134" id="js-post-1454134" itemscope itemtype="https://schema.org/Answer" itemid="https://www.electro-tech-online.com/posts/1454134/"> <meta itemprop="parentItem" itemscope itemid="https://www.electro-tech-online.com/threads/relay-clicking-periodically-when-ignition-is-off.166396/" /> <span class="u-anchorTarget" id="post-1454134"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" itemprop="author" itemscope itemtype="https://schema.org/Person" itemid="https://www.electro-tech-online.com/members/xiaohao76.326639/"> <meta itemprop="url" content="https://www.electro-tech-online.com/members/xiaohao76.326639/" /> <div class="message-avatar "> <div class="message-avatar-wrapper"> <a href="/members/xiaohao76.326639/" class="avatar avatar--m avatar--default avatar--default--dynamic" data-user-id="326639" data-xf-init="member-tooltip" style="background-color: #d6b85c; color: #66531a"> <span class="avatar-u326639-m" role="img" aria-label="xiaohao76">X</span> </a> </div> </div> <div class="message-userDetails"> <h4 class="message-name"><a href="/members/xiaohao76.326639/" class="username " dir="auto" data-user-id="326639" data-xf-init="member-tooltip"><span itemprop="name">xiaohao76</span></a></h4> <h5 class="userTitle message-userTitle" dir="auto" itemprop="jobTitle">New Member</h5> </div> <span class="message-userArrow"></span> </section> </div> <div class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454134" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-09T09:26:32-0700" data-time="1723220792" data-date-string="Aug 9, 2024" data-time-string="9:26 AM" title="Aug 9, 2024 at 9:26 AM" itemprop="datePublished">Aug 9, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454134" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454134/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454134" rel="nofollow"> #7 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454134" data-lb-caption-desc="xiaohao76 · Aug 9, 2024 at 9:26 AM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper"><blockquote data-attributes="member: 273344" data-quote="rjenkinsgb" data-source="post: 1454123" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-title"> <a href="/goto/post?id=1454123" class="bbCodeBlock-sourceJump" rel="nofollow" data-xf-click="attribution" data-content-selector="#post-1454123">rjenkinsgb said:</a> </div> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> My initial guess would be a corroded connectors somewhere with leakage between the pins.<br /> Or, that a module on one of the data bus circuits is not shutting down properly - which could have the same cause, or it could be a faulty module.<br /> <br /> Check all the fuses are OK to start with.<br /> <br /> One test method for modules not shutting down is to use a multimeter on the millivolts range and measure across the testpoints in the top of each fuse. It will be non zero on any fuses that are passing current - then look what that fuse relates to in the fuse chart.<br /> <br /> Do that with the two relays out, so you are not reading the current they take.<br /> <br /> <br /> Also check for any sign of water ingress anywhere, under the carpets or below the boot lining. If there is any trace it has been damp, look for any connectors that may have been affected in those areas - clean and dry them thoroughly, then treat the contacts with deoxit and the outside with WD40. </div> <div class="bbCodeBlock-expandLink js-expandLink"><a role="button" tabindex="0">Click to expand...</a></div> </div> </blockquote>I bought a multimeter to test today, with my very limited knowledge haha.<br /> <br /> What I noticed was that, many fuses have a reading of 12+ volts. I suppose this is because there is still power from the battery to the fuses?<br /> <br /> There are some fuses that are ~0.5 volt. And when the relay clicked, it increased to ~1 volt then drop back to 0.5 volt.<br /> I'm not sure what I should be looking out for <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite10" alt=":oops:" title="Oops! :oops:" loading="lazy" data-shortname=":oops:" /><br /> <br /> I also checked for water traces, but there doesn't seem to be any.<br /> <br /> I troubleshoot further by pulling the fuse out one by one. I noticed the following:<br /> - Pulling out ECU 1 fuse, both main and fuel pump relay stopped. and when it was plugged back in, no further clicking was heard. But issue will re-surface once the ignition is turned on and off again.<br /> - Pulling out SNSR 2 fuse, the fuel pump relay stopped clicking.<br /> - Pulling out the fuel pump fuse, it was surprising to me that the fuel pump relay did not stop clicking.<br /> <br /> Does my above observation tells us anything? I checked the owner's manual and the SNSR 2 fuse if for the following: Oil Control Valve (#1, #2), Camshaft Position Sensor (Intake, Exhaust), F/PUMP Relay,C/FAN LO Relay, Immobilizer Module</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> <div class="message-lastEdit"> Last edited: <time class="u-dt" dir="auto" datetime="2024-08-09T10:44:35-0700" data-time="1723225475" data-date-string="Aug 9, 2024" data-time-string="10:44 AM" title="Aug 9, 2024 at 10:44 AM" itemprop="dateModified">Aug 9, 2024</time> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454134"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score js-voteCount" data-score="0">0</span> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--down " data-vote="down"><span class="u-srOnly">Downvote</span></a> </div> </div> </div> </div> </article> <article class="message message--post js-post js-inlineModContainer " data-author="rjenkinsgb" data-content="post-1454140" id="js-post-1454140" itemscope itemtype="https://schema.org/Answer" itemid="https://www.electro-tech-online.com/posts/1454140/"> <meta itemprop="parentItem" itemscope itemid="https://www.electro-tech-online.com/threads/relay-clicking-periodically-when-ignition-is-off.166396/" /> <span class="u-anchorTarget" id="post-1454140"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" itemprop="author" itemscope itemtype="https://schema.org/Person" itemid="https://www.electro-tech-online.com/members/rjenkinsgb.273344/"> <meta itemprop="url" content="https://www.electro-tech-online.com/members/rjenkinsgb.273344/" /> <div class="message-avatar "> <div class="message-avatar-wrapper"> <a href="/members/rjenkinsgb.273344/" class="avatar avatar--m" data-user-id="273344" data-xf-init="member-tooltip"> <img src="/data/avatars/m/273/273344.jpg?1529068710" srcset="/data/avatars/l/273/273344.jpg?1529068710 2x" alt="rjenkinsgb" class="avatar-u273344-m" width="96" height="96" loading="lazy" itemprop="image" /> </a> </div> </div> <div class="message-userDetails"> <h4 class="message-name"><a href="/members/rjenkinsgb.273344/" class="username " dir="auto" data-user-id="273344" data-xf-init="member-tooltip"><span itemprop="name">rjenkinsgb</span></a></h4> <h5 class="userTitle message-userTitle" dir="auto" itemprop="jobTitle">Well-Known Member</h5> <div class="userBanner userBanner userBanner--gray message-userBanner" itemprop="jobTitle"><span class="userBanner-before"></span><strong>Most Helpful Member</strong><span class="userBanner-after"></span></div> </div> <span class="message-userArrow"></span> </section> </div> <div class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454140" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-09T14:25:16-0700" data-time="1723238716" data-date-string="Aug 9, 2024" data-time-string="2:25 PM" title="Aug 9, 2024 at 2:25 PM" itemprop="datePublished">Aug 9, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454140" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454140/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454140" rel="nofollow"> #8 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454140" data-lb-caption-desc="rjenkinsgb · Aug 9, 2024 at 2:25 PM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper">If you are reading 0.5 - 1V on fuses that should be unpowered, the problem could be a loose or corroded body / chassis ground connection somewhere.<br /> <br /> Look for any wires to bolts on the bodywork, that could be corroded - or have not had the point removed when being assembled. Check they are tight or clean them and re-assemble.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454140"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score js-voteCount" data-score="0">0</span> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--down " data-vote="down"><span class="u-srOnly">Downvote</span></a> </div> </div> </div> </div> </article> <article class="message message--post js-post js-inlineModContainer " data-author="Diver300" data-content="post-1454144" id="js-post-1454144" itemscope itemtype="https://schema.org/Answer" itemid="https://www.electro-tech-online.com/posts/1454144/"> <meta itemprop="parentItem" itemscope itemid="https://www.electro-tech-online.com/threads/relay-clicking-periodically-when-ignition-is-off.166396/" /> <span class="u-anchorTarget" id="post-1454144"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" itemprop="author" itemscope itemtype="https://schema.org/Person" itemid="https://www.electro-tech-online.com/members/diver300.73824/"> <meta itemprop="url" content="https://www.electro-tech-online.com/members/diver300.73824/" /> <div class="message-avatar "> <div class="message-avatar-wrapper"> <a href="/members/diver300.73824/" class="avatar avatar--m avatar--default avatar--default--dynamic" data-user-id="73824" data-xf-init="member-tooltip" style="background-color: #9933cc; 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I suppose this is because there is still power from the battery to the fuses? </div> <div class="bbCodeBlock-expandLink js-expandLink"><a role="button" tabindex="0">Click to expand...</a></div> </div> </blockquote><br /> The feed to something like the fuel pump will go through the fuse and the relay, but that can be in either order. If the power goes to the fuse first, the fuse will be powered all the time.<br /> <br /> If you measure the voltages on the relay contacts, that will be 12 Volts when the fuse is in place and will drop when the fuse is removed.<br /> <br /> The relays are there because some control module is not capable of supplying enough current to power the load, so a relay is used. The fuse only supplies the relay contacts and the load. The relay coil is powered by the control module, so you still hear the click when the fuse is removed.<br /> <br /> Some relays are have one side of the coil connected to ground, and the module turns the 12 V on and off. Other relays have one side of the coil connected to to 12 V and the module turns the negative to the relay on and off.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> <aside class="message-signature"> <div class="bbWrapper"><a href="http://twitter.com/mtrak_uk" target="_blank" class="link link--external" rel="nofollow ugc noopener">http://twitter.com/mtrak_uk</a></div> </aside> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454144"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score js-voteCount" data-score="0">0</span> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--down " data-vote="down"><span class="u-srOnly">Downvote</span></a> </div> </div> </div> </div> </article> <article class="message message--post js-post js-inlineModContainer " data-author="Terry_g" data-content="post-1454149" id="js-post-1454149" itemscope itemtype="https://schema.org/Answer" itemid="https://www.electro-tech-online.com/posts/1454149/"> <meta itemprop="parentItem" itemscope itemid="https://www.electro-tech-online.com/threads/relay-clicking-periodically-when-ignition-is-off.166396/" /> <span class="u-anchorTarget" id="post-1454149"></span> <div class="message-inner"> <div class="message-cell message-cell--user"> <section class="message-user" itemprop="author" itemscope itemtype="https://schema.org/Person" itemid="https://www.electro-tech-online.com/members/terry_g.308605/"> <meta itemprop="url" content="https://www.electro-tech-online.com/members/terry_g.308605/" /> <div class="message-avatar "> <div class="message-avatar-wrapper"> <a href="/members/terry_g.308605/" class="avatar avatar--m" data-user-id="308605" data-xf-init="member-tooltip"> <img src="/data/avatars/m/308/308605.jpg?1615732531" srcset="/data/avatars/l/308/308605.jpg?1615732531 2x" alt="Terry_g" class="avatar-u308605-m" width="96" height="96" loading="lazy" itemprop="image" /> </a> </div> </div> <div class="message-userDetails"> <h4 class="message-name"><a href="/members/terry_g.308605/" class="username " dir="auto" data-user-id="308605" data-xf-init="member-tooltip"><span itemprop="name">Terry_g</span></a></h4> <h5 class="userTitle message-userTitle" dir="auto" itemprop="jobTitle">New Member</h5> </div> <span class="message-userArrow"></span> </section> </div> <div class="message-cell message-cell--main"> <div class="message-main js-quickEditTarget"> <header class="message-attribution message-attribution--split"> <ul class="message-attribution-main listInline "> <li class="u-concealed"> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454149" rel="nofollow" itemprop="url"> <time class="u-dt" dir="auto" datetime="2024-08-10T07:51:43-0700" data-time="1723301503" data-date-string="Aug 10, 2024" data-time-string="7:51 AM" title="Aug 10, 2024 at 7:51 AM" itemprop="datePublished">Aug 10, 2024</time> </a> </li> </ul> <ul class="message-attribution-opposite message-attribution-opposite--list "> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454149" class="message-attribution-gadget" data-xf-init="share-tooltip" data-href="/posts/1454149/share" aria-label="Share" rel="nofollow"> <i class="fa--xf fal fa-share-alt" aria-hidden="true"></i> </a> </li> <li> <a href="/threads/relay-clicking-periodically-when-ignition-is-off.166396/post-1454149" rel="nofollow"> #10 </a> </li> </ul> </header> <div class="message-content js-messageContent"> <div class="message-userContent lbContainer js-lbContainer " data-lb-id="post-1454149" data-lb-caption-desc="Terry_g · Aug 10, 2024 at 7:51 AM"> <article class="message-body js-selectToQuote"> <div itemprop="text"> <div class="bbWrapper">Some good info here! Definitely clean all the battery power and ground connections. I still strongly suggest getting the vehicle scanned. You could be looking for the proverbial needle in a haystack.</div> </div> <div class="js-selectToQuoteEnd"> </div> </article> </div> </div> <footer class="message-footer"> <div class="message-microdata" itemprop="interactionStatistic" itemtype="https://schema.org/InteractionCounter" itemscope> <meta itemprop="userInteractionCount" content="0" /> <meta itemprop="interactionType" content="https://schema.org/LikeAction" /> </div> <div class="reactionsBar js-reactionsList "> </div> <div class="js-historyTarget message-historyTarget toggleTarget" data-href="trigger-href"></div> </footer> </div> </div> <div class="message-cell message-cell--vote"> <div class="message-column"> <div class="contentVote js-contentVote " data-xf-init="content-vote" data-content-id="post-1454149"> <meta itemprop="upvoteCount" content="0" /> <a href="javascript:" class="contentVote-vote is-disabled contentVote-vote--up " data-vote="up"><span class="u-srOnly">Upvote</span></a> <span class="contentVote-score 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While resting in my car with the ignition off, I noticed there's a knocking sound coming from the back off my car periodically. Initially, I ignored the sound and didn't think much about it. It was until I faced a problem where I was unable to start the car when the car was not driven for ~3 days, as the battery level was low and needed a jumpstart.\n\nI started looking deeper into what could be draining the car battery within a few days (the battery is new). Unplugging the car cam did not help and I had to jumpstart the car on a second occasion.\n\nThen I remember the knocking sound which I was hearing periodically with the engine off and suspected that could be the cause of battery drain. The knocking sound could be heard every 13 seconds. Guessing the sound was coming from the fuel pump, I opened up the fuse box. And true enough, the fuel pump relay could be heard clicking every 13 seconds. I unplugged the fuel pump relay, and the knocking stopped.\n\nWith the fuel pump relay unplugged, now I could hear another sound coming from around the engine (again every 13 seconds). So this time, I unplugged the main relay and the sound stopped.\n\nSo it seems like every 13 seconds, there is something powering up the main relay, which is also powering up the fuel pump relay and a few other components and it's draining the battery.\n\nWould anyone be able to advise what could be the problem? Is this normal?", "answerCount": 9, "upvoteCount": 0, "author": { "@type": "Person", "@id": "https://www.electro-tech-online.com/members/xiaohao76.326639/", "name": "xiaohao76", "url": "https://www.electro-tech-online.com/members/xiaohao76.326639/" }, "suggestedAnswer": [ { "@type": "Answer", "datePublished": "2024-08-10T14:51:43+00:00", "url": "https://www.electro-tech-online.com/posts/1454149/", "text": "Some good info here! Definitely clean all the battery power and ground connections. I still strongly suggest getting the vehicle scanned. You could be looking for the proverbial needle in a haystack.", "upvoteCount": 0, "author": { "@type": "Person", "@id": "https://www.electro-tech-online.com/members/terry_g.308605/", "name": "Terry_g", "url": "https://www.electro-tech-online.com/members/terry_g.308605/" } }, { "@type": "Answer", "datePublished": "2024-08-10T07:45:09+00:00", "url": "https://www.electro-tech-online.com/posts/1454144/", "text": "Pulling out the fuel pump fuse, it was surprising to me that the fuel pump relay did not stop clicking.\n\n\nWhat I noticed was that, many fuses have a reading of 12+ volts. I suppose this is because there is still power from the battery to the fuses?\n\n\nThe feed to something like the fuel pump will go through the fuse and the relay, but that can be in either order. If the power goes to the fuse first, the fuse will be powered all the time.\n\nIf you measure the voltages on the relay contacts, that will be 12 Volts when the fuse is in place and will drop when the fuse is removed.\n\nThe relays are there because some control module is not capable of supplying enough current to power the load, so a relay is used. The fuse only supplies the relay contacts and the load. The relay coil is powered by the control module, so you still hear the click when the fuse is removed.\n\nSome relays are have one side of the coil connected to ground, and the module turns the 12 V on and off. Other relays have one side of the coil connected to to 12 V and the module turns the negative to the relay on and off.", "upvoteCount": 0, "author": { "@type": "Person", "@id": "https://www.electro-tech-online.com/members/diver300.73824/", "name": "Diver300", "url": "https://www.electro-tech-online.com/members/diver300.73824/" } }, { "@type": "Answer", "datePublished": "2024-08-09T21:25:16+00:00", "url": "https://www.electro-tech-online.com/posts/1454140/", "text": "If you are reading 0.5 - 1V on fuses that should be unpowered, the problem could be a loose or corroded body / chassis ground connection somewhere.\n\nLook for any wires to bolts on the bodywork, that could be corroded - or have not had the point removed when being assembled. Check they are tight or clean them and re-assemble.", "upvoteCount": 0, "author": { "@type": "Person", "@id": "https://www.electro-tech-online.com/members/rjenkinsgb.273344/", "name": "rjenkinsgb", "url": "https://www.electro-tech-online.com/members/rjenkinsgb.273344/" } } ] }, "publisher": { "@type": "Organization", "name": "Electronics Forum (Circuits, Projects and Microcontrollers)", "description": "An electronics forum to talk all about circuits and projects.", "url": "https://www.electro-tech-online.com" } } </script>  <noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-MMC9PJ9" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>   <noscript><iframe src="https://www.googletagmanager.com/ns.html?id=GTM-KLX5R59" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>  <script> $(function(){ var notice = $('.xb-welcome-notice'); if(notice.length){ var cookie = XF.Cookie.get('hide_welcome_notice'); if(!cookie){ XF.Cookie.set('hide_welcome_notice', Date.now()); notice.show(); } else if ((Date.now() - cookie) > 8.64e+7){ XF.Cookie.set('hide_welcome_notice', Date.now()); notice.show(); } else { notice.hide(); } } }); </script> </div> </body> </html>

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Relay "clicking" periodically when ignition is off | Electronics Forum (Circuits, Projects and Microcontrollers)