Heated mirrors and heated rear screen

[stevo8375]

Mine had cloth tape but the wires were broken. Why dont you try taking some measurments on the defroster grid

You dont have any errors stored in bcm?

What happens when you turn the knob on the mirrors to defrost position?

Maybe it’s worth me opening the cloth tape then and seeing the condition of the loom

No errors in central electronics

If you turn the heating in for mirrors nothing happens, no voltage at mirror glass and I’ve tried the fuse and a new switch

[amer6R]

Id give it a go
But in 99% it would return a fault dear defroster open circuit

Sorry maybe you mentioned it, but did you buy the car like this or it worked in past?

[stevo8375]

No it’s never worked since I got it

[amer6R]

Check in Long coding if it's enabled. - Maybe there is an wire-ing connections and someone disabled the option so it doesnt pop a dtc fault.
I think under adaptations you can set the timer for how long the defrost function is going to be ON.

viewtopic.php?t=75392&start=45

check ciclos post

[stevo8375]

Check in Long coding if it's enabled. - Maybe there is an wire-ing connections and someone disabled the option so it doesnt pop a dtc fault.
I think under adaptations you can set the timer for how long the defrost function is going to be ON.

viewtopic.php?t=75392&start=45

check ciclos post

Thanks for your help, I’ll have a look and see what I can find

[stevo8375]

On long coding it says

Rear window heater activation via can Active

Mirror heating on while rear window heating on Active

Rear window heater Installed

Heated mirrors Installed

[amer6R]

The long coding part is good, no one disabled it.


Id give that loom a look.

so fuse 24 is new
and fuse 53 new

There is a earth connection point on left C pillar for the rear boot lid electronics

image_2023-02-28_152027153.png (82.81 KiB) Viewed 1496 times

heater.PNG (95.24 KiB) Viewed 1496 times

[stevo8375]

Your a legend, I’ll have a look at the loom..might weekend before I get chance

[stevo8375]

I’m at a loss, I’ve checked the loom to the tailgate and it’s fine, no broken wires. Changed the fuses again just in case and still nothing. It’s all very strange

All other tailgate electrics are working fine

[amer6R]

Hmm,
I'm not sure. If there is a fuse for the BCM on the fuse holder that is on battery.
What do you think about disassembling the fuse box on battery 10 mm nuts an clean it very well ( sandpaper or wire wheel). Also clean the contact on the small fuse box ( its sits clipped) I had an issue no-communication to module because it was a bit dirty ( high resistance)

[stevo8375]

Mine is the gti version so the battery is located in the boot, there are some electronics in the engine bay and also some (I think) attached to the side of the battery. Not 100% sure.

[stevo8375]

I was just reading an old thread regarding the heating of the mirrors, could it be a combination of bit 2 and 3 in the long coding as to why mine arent working do you think?

viewtopic.php?t=78020

[amer6R]

Do a full autoscan and save it.
Also save long coding from you BCM. ( So you have double backup).
Then edit those two bits. If it doesnt help you can always revert to old settings.

Yeah you will still have fuses under the bonnet as far as i know.