2004 Monte SS 3.8 rear defogger does not work, light comes on, relay works, has power, grid looks intact? Any ideas Also, there is an plug in top upper drivers side maybe inch long 1/4 inch wide has power where cables go in but not where it clips. What is this part? is it part of the radio antennae? car is not equiped with onstar so it is not that.

Any help is greatly appreciated.

 

That is for radio, Onstar is on the roof.

 

Thank you, I e-mailed the dealership this question and he replied with the Onstar Antennae. So it has nothing to do with the defroster...back to trying to solve the puzzle. Thank you again.

 

I have a problem with my '04 Monte and the rear defroster not working. One common problem is the tabs that the wire connects to the rear glass have lost their connection to the grid on the glass and need re-soldered (not the problem I have). I started a thread on this topic (as all my research ends with no resolve). Thanks to some input on the thread I started, I think I might have my answer (will no later when I rip into the car). Behind one of the rear quarter interior trim panels is a "module" the does some stuff with the radio and the rear defroster. It stands to reason this module may have failed.

Here is the post I started on the subject:
https://montecarloforum.com/forum/ge...froster-24836/

Here is a link to the troublshooting chart for the defroster:
http://sm.gpona.com:9001/si/showDoc....m&cellId=58304

And here's a link about the module in the back that I mentioned:
http://sm.gpona.com:9001/si/cellHand...211419&from=sm

 

Still not working, took to dealer they state open wire. My dad checked things out could not find an open wire. So checked the circuit breaker. Breaker not blown works in power seat, it does however get extremely hot within a minute of being on, hot enough to blister, then shuts itself off. What is the fix for this? Swaped the power seat breaker and it does the same thing.

Any suggestions?

Thanks much.

 

Going back to my post on 4/19/2011, did you have the module behind the rear interior trim checked out? Click the link below to check a thread I started a while ago about Defroster issues:
Click Here --> https://montecarloforum.com/forum/ge...froster-24836/

Defroster issues are common on these cars. Sadly, I never got to rip my Monte apart and swap the module out. But I've done similair testing as you have done and I'm at the point it has to be the module behind the rear quarter trim panel. Unfortunately, the GM information I have barely documents the part and troubleshooting it. Best advise, take the trim apart, get the module out, go to a dealer and tell them it needs replaced. I've checked with a guy who works at a dealership, there are two different part numbers for the module and it's roughly $20-$30.

 

I will let my dad know about this. He has checked out this module before so he knows where it is. Then went to the fuse box, relay's and fuses are fine, has power there none going out of the fuse box. This module could cause the circuit breaker to get so hot it shuts down? The defogger works for that minute or less.