This is more than likely two or more different problems, but I am mostly trying to think tank this. Professionals have been stumped including GM Dealer. I have some thoughts, but mostly need help and guidance. Outlined issues below. Pray for your sanity if I am not able to make this make sense.
The VATS and P0380 codes persist, but the transmission has degraded now even worse (truck has only had 5K miles on it since the rebuild). Seeking, poor shifted up and down. I am beginning to think this is a harness issue with the TCM. I know I need to get the P0380 cleared first so the CEL stops coming on, but the security light is dumbfounding me since the truck still starts and drives and the VATS relearn never happens.
To add to that...truck was almost stolen so I had to replace the whole ignition switch, tumbler, and keys. Again, truck still starts even though now I have a whole new key, switch, and tumbler.
Will post updated codes after I repair the P0380, check all the modules signals at the comb for 7V signal, and attempt the VATS relearn again. But for now, here is what I have before, and after clearing codes. Note the time stamps to tell the difference.
- Transmission began dump shifting in and out of 3rd gear. Very harshly and dramatically. Started out as only after long highway drives. Took it into Inglewood and they were not able to replicate it and said everything was fine.
- Symptoms got worse and took it in again and this time had the trans cracked open. Determined that clutches looked OK but did show more wear on 3rd gear packs. Got the full rebuild since the truck was already apart. TC, Transgo, and fresh rebuild.
- Symptoms improved, but still persisted. Tried to do the trans relearn but kept getting blocked (per tech and trans rebuilder) due to the code being thrown by the VATS (security light) and a different issue I have (P0380) with my glowplug circuit.
- Attempted to rectify that, to no avail.
The VATS and P0380 codes persist, but the transmission has degraded now even worse (truck has only had 5K miles on it since the rebuild). Seeking, poor shifted up and down. I am beginning to think this is a harness issue with the TCM. I know I need to get the P0380 cleared first so the CEL stops coming on, but the security light is dumbfounding me since the truck still starts and drives and the VATS relearn never happens.
To add to that...truck was almost stolen so I had to replace the whole ignition switch, tumbler, and keys. Again, truck still starts even though now I have a whole new key, switch, and tumbler.
Will post updated codes after I repair the P0380, check all the modules signals at the comb for 7V signal, and attempt the VATS relearn again. But for now, here is what I have before, and after clearing codes. Note the time stamps to tell the difference.
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