2004 silverado climatroblem

billtex wrote:

Gaetan wrote:
What is the cure ?
Gaetan

Switch seats with passenger as required?

Nope. that doesn't solve the problem.

Replacing the "aspirator" will, "if" that's what the problem is.

Gaetan wrote:
What is the cure ?
Gaetan

Switch seats with passenger as required?

Thanks for the info. I had this happen recently on my 2004 GMC. Restarted and it hasn't happened since.

It's probably the aspirator....
it's the little vent looking thing above the driver's head.

It has a temp sensor in it, and a tiny fan that draws air across it to monitor "cabin air temperature"

The Chevy truck forums have info about it, which is where I found out about the problem.

When the aspirator craps out, the temperature control goes wonky

I have the same problem with my 2003 daily driver.

Occasionally, it will start blasting the heat on FULL through the driver side vents. Next time I start the truck it is fine.

It is a known issue with the blend door actuators in the ventilation system. Parts are expensive, and it is difficult to fix because you have to take apart the entire dash to get to it.

There is tons of information on google about it.

For me the repair is not worth it because the truck is basically worthless. Only base functionality repairs from here on out.

While I don't have climate control on my truck I do have the split controls. Whenever I disconnect the battery for more than a few minutes the temp control blows only hot air on the driver side when I hook the battery back up. The passenger side works just fine.

The first time it happened the dealer flashed the computer (under warranty) and it was OK after that, until the next time I disconnected the battery. Now after a certain number of starts (I never counted) the blend doors go back to working properly. I have also heard that the gear that operates the blend door can crack but that does not sound like your problem.

Another fix I have read about but not tried is to remove the relay for the HVAC for an hour then put it back in. Somehow this will reset the blend door actuator. If you Google it you'll see it's a very common issue.

Mike