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Any help is appreciated this truck has been through 3 different shops they made a mess of wiring got most back to stock but still no can bus communication
35 mega ohm between 6 and 14 with gateway module disconnected drops to 5 mega ohms and no high speed communication at all on any module on the network tested resistor back by tbcm 120ohm checked internal pcm resistance 122ohm and yes have a scope
Figure I'd close this question as stated truck was a mess put all wires in the can circuit back to stock wiring configuration found pins damaged on bcm pcm gpcm ebcm tbc from using improper tools to test connections ends at connectors after repairing those terminals many discontinued from gm particularly the gpcm used used terminals out of connectors from salvage yard 😀 then once can communication restored in bcm ebcm tbc found pcm tcm gpcm still offline traced out can lines to gpcm to tcm then to pcm found pcm was already replaced by previous shop or shop before last reinstalled original pcm communication not present but no crank ya they keep coming with this truck found crank output wire at pcm was broken in pcm connector repaired truck cranks and starts I had to relearn security of course with original pcm while running various u codes would pop up in various modules bcm tbcm ebcm found when checking can lines in the chain between modules ebcm was pulling can low circuits down replaced ebcm reprogrammed it and whollah truck is fully repaired nightmare good bye thanks all for the help
The following user(s) said Thank You: Noah, Paul P.
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