{"id":21453,"date":"2026-07-31T14:39:24","date_gmt":"2026-07-31T18:39:24","guid":{"rendered":"https:\/\/gm-techlink.com\/?p=21453"},"modified":"2026-07-31T14:39:24","modified_gmt":"2026-07-31T18:39:24","slug":"high-resistance-on-grounds-g103a-g103b","status":"publish","type":"post","link":"https:\/\/gm-techlink.com\/?p=21453","title":{"rendered":"High Resistance on Grounds G103A, G103B"},"content":{"rendered":"<p>Some 2024-2026 Silverado 2500HD\/3500HD and Sierra 2500HD\/3500HD trucks may have several communication issues and CAN Bus errors as well as multiple illuminated warning MILs and messages on the Driver Information Center while the vehicle is running\/driving\/idling. The vehicle also may lose communication with the Electronic Brake Control Module. Several DTCs may be set, including DTC B1980 (No Environment Identifier Received From Brake System Control Module 1) and communication DTCs U1610, U0121, U2418, U2419, U160F, U0101, U0131, U1611 and U0401.<\/p>\n<p>These conditions may be caused by high resistance to ground on grounds G103A and G103B of the body wiring harness. These grounds are located under the hood on the inboard side of the left body structure of the HD trucks, next to the X50A\u2009Engine Wiring Harness Junction Block. (Fig. 16)<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center;\"><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter size-full wp-image-21454\" src=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F16-Ground-1.png\" alt=\"\" width=\"740\" height=\"480\" srcset=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F16-Ground-1.png 740w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F16-Ground-1-300x195.png 300w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F16-Ground-1-85x55.png 85w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F16-Ground-1-200x130.png 200w\" sizes=\"(max-width: 740px) 100vw, 740px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Fig. 16<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>Clean the mating surface on the body structure for these grounds and confirm proper system operation. (Fig. 17)<\/p>\n<p>&nbsp;<\/p>\n<p style=\"text-align: center;\"><img decoding=\"async\" class=\"aligncenter size-large wp-image-21455\" src=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-1024x630.png\" alt=\"\" width=\"740\" height=\"455\" srcset=\"https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-1024x630.png 1024w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-300x185.png 300w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-768x473.png 768w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-89x55.png 89w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-780x480.png 780w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2-1160x714.png 1160w, https:\/\/gm-techlink.com\/wp-content\/uploads\/2026\/07\/F17-Ground-2.png 1214w\" sizes=\"(max-width: 740px) 100vw, 740px\" \/><\/p>\n<p style=\"text-align: center;\"><strong>Fig. 17<\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>Refer to Bulletin #26-NA-202 for more information.<\/p>\n<p>&nbsp;<\/p>\n<p><em>&#8211; Thanks to Kevin Minor<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Some 2024-2026 Silverado 2500HD\/3500HD and Sierra 2500HD\/3500HD trucks may have several communication issues and CAN Bus errors as well as multiple illuminated warning MILs and messages on the Driver Information [&hellip;]<\/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":[238],"tags":[],"class_list":["post-21453","post","type-post","status-publish","format-standard","hentry","category-2026-july-b"],"_links":{"self":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/21453","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=21453"}],"version-history":[{"count":1,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/21453\/revisions"}],"predecessor-version":[{"id":21456,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=\/wp\/v2\/posts\/21453\/revisions\/21456"}],"wp:attachment":[{"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=21453"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21453"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gm-techlink.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}