No start after replace wire harness and fuse box (under hood)
original diagnosis revealed the front fuse box was preventing proper connection for the AC electric (condenser) fan - replace with a new factory unit that included part of the wiring harness - we verified all grounds and power supply to the PCM
no communication with PCM, ABS, AIRBAG, OCSM, INST CLUSTER, GEM, STEERING (all high can) We have tried to unplug the modules without communication.
see attached video of the high can - KOEO and Key off.
The Key OFF is the left video
Key ON is the Right VIdeo
Kind of seems like your missing the acc/run supply. I'd check for missing relay/fuse and the wiring from the BJB.
As the file uploader sometimes changes file order, could you clarify whether the KOEO video is on the left or right?
Key OFF is the left video Key ON is the Right VIdeo
This looks like CAN + and - are switched for some modules or a network branch: diag.net/file/f3s8we5nj… Some modules talk as intended, some talk in the inverse way. Wiring diagram with the section of the harness that got replaced marked could be helpful…
Hi Frank, Just stating the obvious here - the only issue was the cooling fan was inop and a factory fuse block was installed. Now there's a communication fault and the vehicle doesn't start/no crank. All those modules, at least for GM would not be just High Speed GMLAN, but also on the Low Speed GMLAN for a few of them. Have you verified that was the correct part? Have you verified all fuses…
Thanks, we did verify part number - we were told update number and the right one - tested resistance on high to low can for a short, none fount - verified all the can wires are in the correct position on the connectors - I will check the Low-speed GMLAN
Check the connectors on the new harness for pushed out pins.
All connector pins have been verified, all the cal lin positions have been verified - All Power and grounds have been verified.
We are still working on this - every connector and pin has been verified - we are starting a warranty claim on the new harness - The power supply relay for the PCM gets warm - voltage drops and resistance is ok -
OK, we took the old harness and plugged in enough to see if the can problem was fixed, it was - i can not explain how or why, looks like a bad harness (ALL connectors were chacked) - new on on the way and should be here end of week - I will repost after verified repaired