4x4 Not Working

[stuckwithgmctruck]

I have a 2000 GMC Sierra 2500 (new body style) and my 4x4 doesn't work. I have had it scanned it comes up as the tccm being the problem. so i bought a used one and put it on but it still doesn't work all the numbers matched however. i was wondering if the TCCM needs to be reprogrammed to my truck or maybe my wiring is bad. I'm running out of options in the last couple months alone i've replaced the entire transfer case, the shift motor as well as the encoder and the front diff actuator. PLease help i'm losing my patience and business!

[sahls01gmc]

Where did you get the TCCM from? Was it verified that it was in good working condition? I'm not sure about the reprogramming, but I would definitely make sure that all of the wiring is in order to check that off of the list.

 

Hard to gauge your enthusiasm for your truck when I read you name.....

 

 

James

[HawkScot]

I have read many posts on 4wd not working and my conclusion for my 98 Yukon is the switch on the dash. I will be calling modulemaster.com in the next day or two and decide if I want them to rebuild my dash switch or purchase a replacement. If you have the push button dash switch, don't over look the switch.

[gmtech4]

hawkeye,his truck is not your truck type and has a code for the switch when they take a crap..

 

joe..theres no code mentioned and the diagnoses for the misdiagnoses of the tccm, please tell us what the code is ..

 

buying used electronics is not good ,"ya get what u pay for" says the saying

[stuckwithgmctruck]

I pulled up some kind of 'U' code and digging deeper and deeper after 5 hours of testing wires i found it was my transfer case shift motor encoder that went bad. for some reason tho my TCCM boxes keep getting fried looks like another wiring problem. I appreciate everyone's help.

 

 

 

hawkeye,his truck is not your truck type and has a code for the switch when they take a crap..

 

joe..theres no code mentioned and the diagnoses for the misdiagnoses of the tccm, please tell us what the code is ..

 

buying used electronics is not good ,"ya get what u pay for" says the saying