99 Tahoe 4x4 not working

[wjburken]

I found the TCCM under the dash, is there any way to test that TCCM before i buy one of them like all the other parts I have been throwing at it.

Try and find someone with a Tech-2 or other body-directional scanner to see what’s going on.

 

[dnt1010]

If this were my +20 year old truck I would make a run to my local salvage yard and pickup the part that I needed from a donor vehicle on the cheap. At 20 years old there will be numerous donor vehicles available. One big advantage of doing this is you that you get to see exactly what holds the part in place, making the swap into your vehicle super quick and easy and without unintentional breaking of plastic clips/plastic plugs etc. Just my personal preference as my vehicle is not going to be running in the 24 hours of Lemans and does not need everything brand new. Man I like that Ford vs Ferrari movie if you have not seen it go rent it now.

 

[Fless]

Try and find someone with a Tech-2 or other body-directional scanner to see what’s going on.

^^^ THIS. It's the only way I was able to figure out what was going on with my '04's 4x4. It didn't have a 'Service 4wd' message, nothing indicating it wasn't working properly, but we were able to exercise the functions and determine what was not working.