Heated rear window not working - mk 4 gt tdi.

[dizzymac]

Hi, I need some help as my heated rear window has suddenly stopped working on my golf gt tdi mk4. I have checked the fuse 25a and its fine,any ideas maybe the switch? Is there a relay for this? I have very limited knowledge on mechanics:o so any help is appreciated.Cheers.:1zhelp:

[M1tchy]

Have a look on the elements in the rear window and look for any damage, they are really thin and fragile so if you have knocked them while loading/unloading you may have damaged them, likewise if you have had any stickers etc on there you may have damaged it as well.

If you can't see anything try a multimeter across the elements to ensure you have a voltage registering.

If you find some damage you can buy a repair kit which is like a metallic paint you just paint over the damaged area to give the circuit continuity again.


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[dizzymac]

Have a look on the elements in the rear window and look for any damage, they are really thin and fragile so if you have knocked them while loading/unloading you may have damaged them, likewise if you have had any stickers etc on there you may have damaged it as well.

If you can't see anything try a multimeter across the elements to ensure you have a voltage registering.

If you find some damage you can buy a repair kit which is like a metallic paint you just paint over the damaged area to give the circuit continuity again.


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Thanks for your reply.I was thinking it could be the element damaged and was thinking I would have to replace the whole screen.

[M1tchy]

No problem. Something like this will do.... Halfords | Granville Rear Heater Repair (http://www.halfords.com/motoring/garage-equipment/auto-electrical-supplies/granville-rear-heater-repair)

And a how to..,.
How to Repair a Rear Defroster : Applying Defroster Repair Compound - YouTube (http://youtu.be/FSPdfjCbHX8)



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[Flash2]

If it was element damage only the damaged elements wouldn't demist. It's unlikely the whole screen would be effected.
But as Mitchy says, the first thing to do would be a voltage test, just because it's easy to do.
Just gently touch your voltmeter probes onto the ends of each element on the inside of the screen. You should get about 14Volts on each one.
Do the test with the engine running. The rear screen heater doesn't work if the alternator isn't charging.

Jim.

[dizzymac]

Thanks for being helpful but someone advised me today it could be a relay so will check that first.

[dizzymac]

Hi Jim,thanks for your reply.I will try what you suggested but gonna check to see if its a dodgy relay first.

[Flash2]

Hi Jim,thanks for your reply.I will try what you suggested but gonna check to see if its a dodgy relay first.

It's been a while since I've worked on a Mk4, so I checked to be sure and there doesn't appear to be a relay in the HRW circuit.
Can you hear a relay clicking when you switch it on? If not, did you in the past when it was working?
Let us know what you find.

Jim.

[dizzymac]

I think your indeed right,I checked and it stated there was no relay in a diesel There hasn't been any clicking noises when switching on. I'm gonna check the wiring in the tailgate shortly so will let you know.

[Flash2]

Check for broken wires in the rubber tubing where the wiring loom enters the tailgate on the passenger side near the tailgate hinge.

[dizzymac]

Yea will do.Cheers.

[dizzymac]

While I'm here I have also had a problem with the climatronic. When its switched on recently its been making a loud like ticking noise which is coming from the passenger side under the glove box.I took it to someone and he said its something that has flaps that controls air intake.He said the teeth in the motor wear.Is he right and is it a big or expensive fix? Cheers.

Daz.

[dizzymac]

Hi Jim,just checked the wiring and a white wire is broke.What would be the best way to repair?

Cheers.

[Flash2]

Climatronic first...the noise will be one of the stepper motors that move the various flaps in the heater box. I've never had to replace any on a Mk4 Golf, but have done a few on old style (B5) Passats and it was a big job.
Also, after the motor has been replaced you need to use the diagnostic scan tool to program the limits of the new motor into the climatronic ECM (Basic Settings).
You can remove the glovebox and see the motors. Try operating the heater controls and see if you can identify which motor is clicking and which control makes the motor move.

As for the wiring repair, my preference would be to solder in a new length of wire but the easiest repair would be to use a crimp on butt connector to join the two ends back together.
If you can find one of the butt connectors that have heat shrink & hot melt glue in them (like the ones the VW dealers use. VW don't like solder) then so much the better.

Jim.

[dizzymac]

Great answers Jim I will take on board what you have said,your feedback is much appreciated!

[Grasmer]

Hi,

I have a similar problem on mine. Theres 2 lines (elements?) that are not working. How do i test just those lines ? put the multimeter probes on top of them while its active? I have looked for damage but i cannot find any breaks on any elements

[Flash2]

Well, if there are only two elements not working then it really has to be due to a break in those elements. You can test with an Ohmmeter (while the heater is off) across the elements to see if they are open circuit (broken).
If some elements are clearing, the power supply and earth to the screen must be OK. Be aware that if your car is a newer model (ie not a MK4 Golf) it can have elements that aren't for heating but are for the radio aerial.
Those are normally the upper 3 or 4 elements on some screens.

Jim.