When I push the rear defrost button the window doesn't defrost at all.

 

Well did you check the fuse?

 

Attached is a diagram of the relay box in the boot. The back light heater relay is for the rear defroster. swap it with one of the relays next to it. If it works them the relay is bad and needs to be replaced.

 

I took out the relay and then put it back in; works again. Not too sure how that made it work again.

 

Ok. I am going to switch the relays and see if that works. But first I'll try taking it out and putting it back in. Let you know what happens.

 

The relays will sometimes loosen up and loose contact. They will also corrode and lose contact. If taking it out and reinstalling it worked for the relay you might want to check and reseat the other relays on the board.

 

Ok thanks. I will do that.

 

The relays are cheap to replace -- $12.

The internal relay contacts could be pitted depending on the frequency of use. The defroster is high amp. The contacts that you can see are rarely the problem -- the internals flex when you pull them out .. often realigning the internals. It may work for a while .. but will fail again.

 

Oh, ok. I'll replace it then. Thanks for the heads up.

 

Don't replace unless you are sure that is the problem?

It's simple to switch out the relay with another one -- and you can easily test the fuse and if power is getting to the window.

 

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