My rear defroster hardly works, if there is more than a light fog on it, it does't work well at all. Occasionally, I will hear some clicking under my dash on the passenger side, just random clicking. I figure there is probably a relay for my rear defogger. Is there? I went to autozone, they looked it up on their computer and told me that my car does not have a relay for the rear defogger. He said it was probably my switch, but my switch seems to work well. Could anyone tell me if there is a relay for my defogger and where it is located? Also, since Autozone says I don't have one, what do I ask for? Thanks, Matt

 

What year and model car do you have?

The Trickster!!!!!!!!!!!!!

 

it is a 1986 pontiac trans am (TPI 305)

 

Hello Matt,

I have checked AutoZone, NAPA, and Advance Auto Parts websites. None of them carry it, I believe that this is a dealer only item. They should also be able to give you a location for it. On mine (1989 Iroc-Z) , it is mounted behind the dash on the passenger side. It is called a defogger control unit or module.

The Trickster!!!!!!!!!!!!!

 

Make sure where the wires attach to the rear lift struts are tight. The OE ones had terminals that were permanetly attached to the cylinder, if they were replaced some types have ligs that kind of float sometimes making for a bad connection causing the relay to cycle on and off. Otherwise most likely the control module is bad.

 

Also check the grid lines across the hatch for any breaks in them.

The Trickster!!!!!!!!!

 

Awesome, thanks for your help, my gridlines are good, its gotta be the module, thanks!