Sarah29wv

Hope you guys can help with this one, we're at a loss. push button switch, 5.3, 2002 LT Tahoe. new 4wd switch, TCCM, 4wd Actuator. It will sometimes switch in and out, sometimes switch and lock into 4wd and then flash "service 4wd". Once this happens the lights on the switch turn off and the only thing that switches it back to 2wd is to disconnect the battery.

As far as we can dig, the folks before us never used 4wd. ABS does not work either, fuse is pulled because it was randomly throwing the ABS when brakes were applied.

strutaeng

You replaced the encoder motor on the transfer case? There's a range sensor inside the encoder motor that can fail, and the system doesn't know where the transfer case has shifted to. Look here, post #11 has some pictures and part numbers:

https://www.performancetrucks.net/fo...essage-560255/

I hope this helps.

Sarah29wv

Have not replaced the encoder motor. I will look at that next and hope thats the fix. Thanks

01WS6/tamu

iTrader: (36)

If you wanna fix it you need a shop grade scanner to read the codes then follow the diagnostics. If not you'll go broke throwing parts at it