Rear Window Heater

[snowjoke]

Noticed this evening with the rear window heater/defogger on, it's only clearing the middle section of the rear window - only looks like about the middle 4 of the horizontal black lines are working. Any ideas what could be wrong?

[Davrav]

Noticed this evening with the rear window heater/defogger on, it's only clearing the middle section of the rear window - only looks like about the middle 4 of the horizontal black lines are working. Any ideas what could be wrong?

Check the tracks closely for breaks/scratches. These can be repaired with a conducting paint - used to be available from Halfords for about £8. Works out about £1/ml but a lot cheaper than a new rear window.

Have a read of these threads:LINK LINK

Good luck

[three5]

Noticed this evening with the rear window heater/defogger on, it's only clearing the middle section of the rear window - only looks like about the middle 4 of the horizontal black lines are working. Any ideas what could be wrong?

Hi Snowjoke,

we had this problem on here 12 months or so ago. It is almost certainly the heater tracks that are broken. The tracks are a metal based paste that is applied with a mask before the screen is toughened. The toughening process ( i.e. heating ) changes the nature of the paste so that it becomes a resistor that heats up when a current is applied. When we last discussed the issue here the concensus seemed to be that you could buy repair paste ( paint ) and apply it to the broken tracks to re-establish conductivity. I have done it in the past but it is some time ago. When the heater is repaired and switched on the heating effect cures the paste.

You need to clean the inside of the screen carefully and then inspect it, probably with a magnifying glas to find the breaks. A multimeter and probes set to resistance can be helpful in finding smaller breaks. If the break is longer than about 1mm it is probably worth using masking to keep the job neat. Also check the wider bits of the tracks at the end and the wiring to make sure that you are getting power to all the tracks. Well worth doing as a new rear screen will be expensive. In my experience it is often dogs claws that do the damage, or sometimes over agressive cleaning.

[snowjoke]

Many thanks for the links and advice. Will get the multimeter out and have a close look!