Hi there
i have a 1990 mk4 xr3i and i am having problems with the heatred screen.
when i turn it on the button lights up but no lick with the screen demisting.
any ideas??????

i would like to change the relay for a new one to see if this is the problem but i cannot find it anywhere???? please help

many thanks

 

I have exactly the same, its the only thing that doesnt work lol.

Just assumed the wire was broke or relay but not got round to it yet.

Let me know if you find a cure and ill do same.

 

If its not a fuse its usually the actual screen... they seem to just pack up after a while!

 

I had thought this as it's the original. Contacts look ok but could just be a break somewhere. Suppose I could test to see if any volts get to either contact when switched on.

Is the light in the switch on a separate fuse to the screen itself? It does light up but it'll probably have a higher amp switch after the relay?

 

Fuse not switch.

 

The fact that the switch works, means you next need to look at the output from the switch to the relay, once the correct relay has been identified take out the relay and using a piece of wire plug across 30 and 87, this will power the screen direct with ignition on, with the engine running you will hear the engine note change as the alternator loads the engine.
A break in 1 wire will not stop the screen working all lines are fed from each side, so unless they are all broken they will work with power.
The relay could have "vorn heiz" written on it for front heat, or "vorn heiz fenster", front heated window, but looking on the legend on the inside of the fusebox lid will show you which one it is, the rear screen will be a squarer shape drawing and the front screen relay will be a shape like a wiper blade sweep area.
tabetha