Rear Window Demister

[Stang]

Hello All!

I am baffled as to why my rear window demister doesn't operate. The light comes on, on the dashboard button, but it doesn't throw the relay under the bonnet. I've tried switching over the relay but the relay doesn't seem to be the issue. If I manually throw the relay, the demister works!

Has anyone else experienced this fault, and obvious question: what's the fix?!

Looking forward to a resolution!
Rupert

[scooter]

Check the switch output side

[Stang]

Thanks Scooter - I assume I would need to remove the switch from the dash to check the output side? Does it just 'snap' out with a screwdriver? I dont want to remove the dashboard!

[greeners]

HRW switch is part of the HVAC ECU and not a seperate item. If you remove the cover panel, there are four screws to remove it



I would try unplugging both connectors and plugging them back in see if that cures it.

Failing that try a battery reset

[peterv8]

Check the connectors at the rear window and measure if there is 12 volt when demister on.

[Stang]

Thanks for the tips, everyone - good to see this forum is alive and well!

I've tried the battery reset, and it's not the connectors at the rear window. That leaves checking the connectors at the back of the ECU

[peterv8]

Thanks for the tips, everyone - good to see this forum is alive and well!

I've tried the battery reset, and it's not the connectors at the rear window. That leaves checking the connectors at the back of the ECU

Is there not a fellow member near you who can lend out his HVAC ECU or try yours in his car? I'll be glad to do it but I'm a bit far from you!:-)

[Stang]

Hi Peter - Actually, you are further than you think; I'm in Dubai! The car is in Bath, UK, and I'm making plans to get it back on the road. There used to be another ZT260 owner in Bath, but it was another lifetime ago!