Hello I have a 2000 blazer that is stuck in 4 hi. I have checked all vaccuum lines, they appear to be in good shape. I replaced the encoder motor that did not fix the problem. the vaccuum switch on the transfer case is also working properly. When I push the 4lo button on the dash the light flashes for 20 t0 30 seconds and then goes off. The light on the 2 hi flashes only when I push the button. the box on the passenger side clicks when the buttons are pushed. any ideas are greatly appreciated.

 

did you unhook the battery for a few minutes to let the tccm reset itself after you put in the new encoder motor? the tccm will store codes and not let the encoder motor go into any other range if it has locked it out

 

I will try that thanks.

 

I tried unhooking the battery for 30 minutes after installing the encoder motor, nothing changed. I installed a different tccm from a different blazer that was working but it didn't work on mine. Could the switches on the dash be a problem? One person told me that a ground strap on the frame might have been damaged or corroded, I couldn't find one where he told me to look any ideas.

 

3-button or 4-button switch in the dash?

3-button = NV233
4-button = NV236

Use those as search terms and you should turn up a number of informative threads on the subject.

 

3 button nv233

 

After all the time and money spent turns out the fuse was blown all is ok now. Thanks for the suggestions