Mk 2 Heated Rear Window not working

Hi all,

Just joined, please be gentle!

I’m having a problem with my heated (glass) rear window in my 1999 1.8 mk2. I’ve had a search on the forum, but couldn’t find the answer.

The button on the dash lights when pressed, but the element doesn’t heat (so doesn’t clear the window). I hear a click from beside the steering wheel when pressing the button (maybe the relay?), and sometimes a chattering when it’s left on.

I’ve read about checking the fuse/relay in the boot, but I couldn’t find either (maybe they’re mk1 thing?), but found the “defog” fuse in the fusebox beside the steering wheel. It is intact, but I don’t know where the relay is. Could someone point me in the right direction/tell me how to check the relay? Do you have any other ideas of what to check?

Many thanks!


The plot thickens!

I’ve just been out with a multmeter. There’s 6-7 volts being delivered to the heating element (in the glass) and 1.5 ohms of resistance across the element. Surely it should work then?! Is 6V enough for the heating element? Is it designed to run on 12V? Am I getting voltage drop somewhere?

Whilst reattaching the spade connections, I also pulled the soldered connection off the window, so I’m going to have to get a soldering iron out!

G’day mate Welcome to the forum–

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Here’s a diagram of the HRW circuits

 It sounds like a faulty relay, the ones in the boot are for the MK 1 model only, yours is behind the dash.



Thanks very much for the help so far, I’ll get onto locating the relay. Do you know exactly where it is (I presume near the fusebox?), or how to test it? To add insult to injury, the car was bought without a manual so I’m a bit blind!

Sig and location amended too.


Hi mate, I’m just having a similar issue. The switch button doesn’t light up when pressed and there’s no clicking noise from behind the dash. I checked the fuse which seems alright, so am thinking it must be a faulty relay. Did you manage to locate yours and if so, can you make a quick picture? Cheers, Nas!