First off im new to this forum so hello! Now down to the business... ive read alot about the 4x4 system and how it works and have been reading about problems similar to mine on this site but i figured it would help me out if i just posted my issue. I have 2004 blazer zr2 with 99k miles. My problem is that when i press the 4hi button both the 4hi and 4lo buttons blink simultaneously and then go back to 2hi. When i press the 4 lo i can hear the transfer case shift and both 4hi and 4lo lights stay lit up. The PO said that he had replaced the encoder motor on the TC and it does look newer than the TC itself. Also i plugged in a working tccm and still the same thing. Any help would be appreciated.

Auston

 

Check the wiring to the transfer case. Make sure all the connections are clean.

 

check the dash switch also. I had just purchased a replacement push button switch to try and resolve an issue with my 4x4. The Dorman switch new out of box would go to 4 hi from 2 hi, but when I pushed 2hi it would go to 4 lo! I picked up 1 cheap at the salvage yard, worked fine