{"id":14887,"date":"2021-06-14T15:59:07","date_gmt":"2021-06-14T19:59:07","guid":{"rendered":"https:\/\/gm-techlink.com\/?p=14887"},"modified":"2021-06-14T15:59:07","modified_gmt":"2021-06-14T19:59:07","slug":"lin-bus-inputs-causing-intermittent-parasitic-draw","status":"publish","type":"post","link":"https:\/\/gm-techlink.com\/?p=14887","title":{"rendered":"LIN Bus Inputs Causing Intermittent Parasitic Draw"},"content":{"rendered":"

A dead battery as well as several other conditions, including slow engine crank, inoperative Auto Stop\/Start (if equipped), radio on or fades out slowly after the ignition is off, and inoperative front or rear heated seats, may be found on some 2019-2020 Silverado 1500 and Sierra 1500 models. LIN Bus DTCs U1524, U1526, U1555, and U155D also may be set.<\/p>\n

These conditions may be caused by the Body Control Module (BCM) staying awake due to an input from a LIN Bus. In many cases, the BCM is misdiagnosed as being at fault and is unnecessarily replaced.<\/p>\n

There are two known areas that can short out LIN Bus circuits 6133 and\/or 4115 for the front\/rear heated seats. If this occurs, the BCM may stay awake and draw down the battery. Keep in mind that even if a truck is not equipped with rear heated seats, these circuits are still in the harness.<\/p>\n

Inspect for a pinched body harness under the left rear seat where the seatback is attached to the back of cab. (Fig. 11)<\/p>\n

 <\/p>\n

\"\"Fig. 11<\/strong><\/p>\n

 <\/p>\n

Connector X370 is shown on a truck that was not equipped with rear heated seats. (F12) In this example, LIN Bus circuit 6133 was shorted to the B+ circuit in the harness.<\/p>\n

 <\/p>\n

\"\"Fig. 12<\/strong><\/p>\n

 <\/p>\n

In addition, inspect connector X225 for terminal issues\/corrosion. As shown, the LIN Bus circuit 4115 was corroded (Fig. 13) and shorting to other terminals in the connector.<\/p>\n

 <\/p>\n

\"\"Fig. 13<\/strong><\/p>\n

 <\/p>\n

If corrosion is found at connector X225, inspect for a water leak. Water may be entering at the A-pillar grommet for the door pass-through connector if the grommet is not fully seated.<\/p>\n

If any issues are found, follow the Wiring and Connector Repair instructions in the appropriate Service Information to correct the condition.<\/p>\n

Refer to #PIT5750A for additional information.<\/p>\n

 <\/p>\n

\u2013 Thanks to Jim Miller<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

A dead battery as well as several other conditions, including slow engine crank, inoperative Auto Stop\/Start (if equipped), radio on or fades out slowly after the ignition is off, and […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[87],"tags":[],"class_list":["post-14887","post","type-post","status-publish","format-standard","hentry","category-2021-june-a"],"_links":{"self":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/14887","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=14887"}],"version-history":[{"count":1,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/14887\/revisions"}],"predecessor-version":[{"id":14888,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/14887\/revisions\/14888"}],"wp:attachment":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=14887"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=14887"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=14887"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}