OP
OP
whtbronco
Full Access Members
Over the last 3 days, I got the transfer removed, the coil replaced, the clutch pack assembly verified correct and I found the reason for it engaging A4WD, 4HI and 4LO, but not disengaging properly and it's reinstalled. It's working fine now.
There's no question the coil was messed up. No buzzing when the PWM is increased now, it engages quickly and properly, disengages instantly and I had 2 scans with no codes found, except the air suspension VDM calibration that's not gonna get resolved. I would never have guessed the shift motor and coil could lead to so many codes for numerous other modules such as mirrors, HEC, PCM(for PATS), EATC, DCSM, DSM, VDM, VSM, TPM, PCSM, ABS and RCM. Clearly the faulty parts were causing issues, maybe bad feedback, for the SCP and UBP circuit buses.
The other issue is that somehow I managed to get the spring for the shift fork rod installed on the shift shaft. That spring pushes the the 4HI shifter fork back down to disengage 4HI when shifted into A4WD or 2WD. That explains why it didn't disengage 4HI consistently and sometimes after driving it would disengage, due to vibration I think. I know where that spring goes, how in the heck did I get that wrong. Either I simply screwed up or my daughter was helping me reassemble last time since I was having some trouble with alignment of the 2 rods and both output shafts. Maybe it fell off when I pulled the rear of the case up to try again and she dropped on the other shaft without me knowing. I dunno, and clearly that was the cause. At least it was an easy fix and the transfer case had to come out for the coil anyway.
Now this thread is done.
There's no question the coil was messed up. No buzzing when the PWM is increased now, it engages quickly and properly, disengages instantly and I had 2 scans with no codes found, except the air suspension VDM calibration that's not gonna get resolved. I would never have guessed the shift motor and coil could lead to so many codes for numerous other modules such as mirrors, HEC, PCM(for PATS), EATC, DCSM, DSM, VDM, VSM, TPM, PCSM, ABS and RCM. Clearly the faulty parts were causing issues, maybe bad feedback, for the SCP and UBP circuit buses.
The other issue is that somehow I managed to get the spring for the shift fork rod installed on the shift shaft. That spring pushes the the 4HI shifter fork back down to disengage 4HI when shifted into A4WD or 2WD. That explains why it didn't disengage 4HI consistently and sometimes after driving it would disengage, due to vibration I think. I know where that spring goes, how in the heck did I get that wrong. Either I simply screwed up or my daughter was helping me reassemble last time since I was having some trouble with alignment of the 2 rods and both output shafts. Maybe it fell off when I pulled the rear of the case up to try again and she dropped on the other shaft without me knowing. I dunno, and clearly that was the cause. At least it was an easy fix and the transfer case had to come out for the coil anyway.
Now this thread is done.
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