service 4wd light

die hard · April 15, 2019

so i got the service 4wd light come on my 2001 2500hd 8.1 .i switch the truck to 4 wheel low and is now stuck in low . the lights on the 4 wheel selector switch are not lite up .they do lite up when i first turn the key on .what i've tried so far is discontented battery for few minutes check atc fuse is good..replace the 4wd selector switch .cleaned the grounds on frame near cab mount .check wire connections to to transfer case and front differential .i replace transfer case few years ago with a GM rebuilt .im lost hoping someone else has had same problem can steer me in right direction on they have done to fix my problem

DeePa · April 15, 2019

It’s probably the shift motor on the transfer case.

04z71crew · April 16, 2019

Had the same problem on my 2004. Turns out it was the sensor inside of the encoder motor mounted to the transfer case. $50 part AC delco on Amazon. Try the sensor first before you shell out the $$ for the entire encoder motor.

die hard · April 16, 2019

1 hour ago, 04z71crew said:

Had the same problem on my 2004. Turns out it was the sensor inside of the encoder motor mounted to the transfer case. $50 part AC delco on Amazon. Try the sensor first before you shell out the $$ for the entire encoder motor.

THANKS ! ill give that a try . pisses me off i should of kept the encoder when i returned my transfer case core few years ago.

die hard · April 20, 2019

On 4/15/2019 at 10:24 PM, die hard said:

THANKS ! ill give that a try . pisses me off i should of kept the encoder when i returned my transfer case core few years ago.

i had to replace the who;e encoder motor assembly ($125) i couldn't find the sensor separate even from the dealer .the motor worked so blame the sensor