Thanks for reading my thread-I hope you can offer some direction.

The rear window defogger on my wife's four door 2001 Alero does not work. Here's a breakdown of what I've learned:

1. I have the factory shop manual and have checked it out.
2. Pushing the button does nothing. No rear defogger. No LED indicating that it is on.
3. Underhood fuses have been checked and are OK.
4. I switched the rear defogger relay (#9) with one of the fan relays as suggested by the manual. This made no difference.
5. The radio appears to work just fine.
6. I have checked the grid to make sure it is connected and connections look good.

All that's really left is the HVAC control, which looks darned expensive, or the module behind the L/R pillar trim panel. I've read where the connector is a fragile arrangment and that this module can fry; but I'd expect the little light on the switch to come on regardless.

Any diagnostic help would be appreciated. The shop manual diagnostic strategy involves largely verfiying the integrity of the various wires and when all else seems to fail, replacing the HVAC control.

Thanks. Lousy winter weather is coming-I'd like this darned thing fixed.

Frank

 

hello I fixed the same problem hrs ago by replacing the whole center unit (heater controls ect) after 8-9 yrs I got my defrosters back so there must of been something wrong with either the button or the circuit board in back of temp control panel, hope this helps, barry