2005 Tahoe encoder motor install question
miscrap
10-09-2011, 10:23 PM
I got the Service 4WD light on my '05 Tahoe Z71. No lights on the selector, couldn't change modes. Truck was driveable, so I believe it was in 2HI. Had the code read, C0327 which indicates the encoder sensor. I found instructions on this site for how to replace it. Everything came apart real easy, got the new sensor installed in the motor. Went to put the motor back on and the shaft had turned, the notch on the shaft no longer matches up with the gear on the motor. The notch on the gear is at around 11 o'clock position, the notch on the shaft is at 6'oclock. I read multiple comments (all apparently quoting the same bulletin) which says to use a crescent wrench to turn the shaft to the necessary position. How? I can turn it to about 9 o'clock, but no further. Plus, it immediately springs back to 6 o'clock. Someone suggested putting the truck in neutral (trans), jacking the rear tires off the ground, and turning the rear driveshaft while I try to turn the shaft. Did that, same results. Right now the truck is in the middle of my driveway, with the front end up on ramps and the rear on jack stands, with no front driveshaft. This is my daily driver, and I'm stranded without it. Does someone have any other suggestions?
j cAT
10-10-2011, 08:09 AM
I got the Service 4WD light on my '05 Tahoe Z71. No lights on the selector, couldn't change modes. Truck was driveable, so I believe it was in 2HI. Had the code read, C0327 which indicates the encoder sensor. I found instructions on this site for how to replace it. Everything came apart real easy, got the new sensor installed in the motor. Went to put the motor back on and the shaft had turned, the notch on the shaft no longer matches up with the gear on the motor. The notch on the gear is at around 11 o'clock position, the notch on the shaft is at 6'oclock. I read multiple comments (all apparently quoting the same bulletin) which says to use a crescent wrench to turn the shaft to the necessary position. How? I can turn it to about 9 o'clock, but no further. Plus, it immediately springs back to 6 o'clock. Someone suggested putting the truck in neutral (trans), jacking the rear tires off the ground, and turning the rear driveshaft while I try to turn the shaft. Did that, same results. Right now the truck is in the middle of my driveway, with the front end up on ramps and the rear on jack stands, with no front driveshaft. This is my daily driver, and I'm stranded without it. Does someone have any other suggestions?
I suspect that the transfercase is in HI 2WD. the encoder when removed should have been in HI 2wd. you stated that this is the same encoder motor with new hall effect sensor installed so , it should go back in. the encoder has a brake in it , so it can not move unless it is powered to release it.
how did the transfercase and encoder get out of position ?
the encoder brake feed is connector C1. pin C is the feed 12volts from the ATC fuse. PIN D is the ground which goes to the shift control module which is the grounded side of the brake/lock solenoid. appling power to this solenoid pin C and grounding PIN D , should allow easy rotation of the encoder to line up the key.
the tan wire is ground the orange is 12 volts.
I suspect that the transfercase is in HI 2WD. the encoder when removed should have been in HI 2wd. you stated that this is the same encoder motor with new hall effect sensor installed so , it should go back in. the encoder has a brake in it , so it can not move unless it is powered to release it.
how did the transfercase and encoder get out of position ?
the encoder brake feed is connector C1. pin C is the feed 12volts from the ATC fuse. PIN D is the ground which goes to the shift control module which is the grounded side of the brake/lock solenoid. appling power to this solenoid pin C and grounding PIN D , should allow easy rotation of the encoder to line up the key.
the tan wire is ground the orange is 12 volts.
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