I have a 2004 Trailblazer EXT LS with the I6.

I recently bought it and noticed that the rear blower is not working. I bought it anyways thinking easy fix.

Here's what I've discovered. Can not find any blown fuses. I have 5v power to the front switch. If I turn key on engine off and turn the rear fan on with the front switch and just leave it for a while, after about 10 minutes the blower will start working and run as long as I don't touch it. But, as soon as I turn the key off and back on, I have to wait 10 minutes again.

If I start the trailblazer and turn the switch on, I have let it run over half an hour and the blower will never turn on.

If I have the key on engine off and turn the front switch to R and the rear switch on, I hear a whirring noise coming from under the center console near the rear HVAC control panel.

I pulled the rear blower out and hooked it direct to battery and it works just fine.

I have checked the resistance in the front switch and also from the plug for the rear control module and the resistance is in specs with what I found on this thread

https://chevroletforum.com/forum/tra...working-42019/

Can anyone tell me either what's wrong or what else to check in order to find the problem?

 

Anybody?

 

Bump?

 

Hi Malachi, It sounds to me as if you have a (pussed) circuit somewhere. Where the wire connection is grounding through corrosion (puss) around the wire usually where the wires are held against the frame or body and rubbed a bit just enough to corrode.