Ish_944

Hi All,

I've been trying to figure out why my rear defroster doesn't work. After endless hours of consultations with the wiring diagrams, I figured out that the 4 mm2 black wire providing ground on the passenger side beetween the strut and the chassis is missing.
This is also why my boot light won't come on upon lifting the hatch.

Where is the ground connection for the defroster? It isn't the same as for the tail lights as per the diagrams. Looking around in the area I couldn't see a spot for it either. Could you please help?

Can someone share a picture of the wiring setup on the passenger side strut? I think I know how it should work, but would be really nice to confirm my theory.

Thanks a lot in advance!

931guru

The black wire comes from the light fixture (blue oval). The path to ground is complete through the strut (red circle).

orig944

The current for the defroster passes like this:

1) left side body wire to strut, strut is insulated where it connects to the body.
2) left strut to defroster through wire
3) defroster to right strut through wire
4) right strut to body ground through ball joint. Strut is conductive where it connects to body.

With the defroster on, you can follow this path through to find where the problem is. It's possible someone put the wrong struts on the car at some time in the past.

Right side wire is for the luggage and door lights. Current passes like this
1) Through light bulb
2) through switch set to "light on when hatch or door open"
3) light switch to right strut switch through skinnier black wire
4) through strut switch to right strut
5) through right strut ball joint to body ground

Coincidentally, yesterday I found my right side wire was broken at the connector. I took the connector apart and soldered the wire where it had been crimped.

orig944

Diagram I did for someone else a while ago....

Ish_944

Thank you gents!

Now I see that I was wrong, there is no cable missing. I did not know that the defroster should ground through the strut.
I had to replace them and originals were not available around here so I went with Quinton Hazel (?) ones, which, at least on datasheets, should be a bit weaker then stock. However, they are both 'left' struts.
So I can get functionality back, because I have the 'hatch open' connector from the old one, but I have to ground the strut myself somehow.

Thanks for your help, I learned again something new!

Tiger03447

I have had the clip that adheres to the defroster grid come loose. I have tried silver epoxies, without success, so has anyone tried double sided conductive tape for reattachment? TIA😀

Ish_944

I actually re-soldered mine. Turned out decent!
I was a bit worried about cracking the window, so I put solder on the contacting side of the clip first, then I heated the whole thing up as much as I could, then pressed it on. Would have been easier if I had 3 arms It worked on the 2nd try. I covered the boot underneath with a towel, just in case.