Hello there,
I have an '02 BLazer s10 LS with a four button auto 4wd transfer case, and my 4wd is not functioning. Whenever I press a button to engage 4wd, the lights in the switch just blink continually. I took it to a family mechanic, and he said my encoder motor was shot and referred me to a transmission shop. They tested my truck, and said my encoder motor was fine, and I needed a new TCCM (model 15748800). I replaced the TCCM (with model 12577412), and this did not repair the issue. Can someone please tell me what model transfer case I have, what encoder motor would work with that, and if there is anything else in this chain I should be looking at? All related fuses have been checked, and replaced just for safety even though they were fine. I don't have a reader, but when we checked the obdii codes, it was flashing 5 or 6 of them, something about shift solenoids a and b, and something else relating to "TCC" which I assume meant the TCCM?

 

How many buttons do you have on your 4wd switch?

What were the specific OBD2 codes that you pulled (Pxxxx)?

 

He stated he had the 4 button 4wd switch in the first line. NV236 transfer case correct?

 

Yes, I missed that. Was reading it too quickly.

You need to pull the codes with a scan tool capable of communicating with the TCCM.

 

I don't have a reader, but off the top of my head using a chart, it was Shift Solenoid A electrical (P0753), Shift Solenoid B electrical (P0758), TCC Enable Solenoid circuit electrical (P0740), and two more I can't recall. At the time this was scanned though, I couldn't get my truck to start or the keys to come out of it either, it was right after I replaced the heater core