hi all, found out this morning that my rear window demister isn't working, not sure how long it hasn't worked as not really needed it since last spring arrived, i have checked the fuse which i believe is a 30 in f14 glovebox fuses and that is fine so i would be grateful for any ideas, thanks in advance stu.

 

Your post doesn't tell what model year you are working on. It makes a difference since there was a change to the electrical system in 2004. If yours is pre 2004 then you need to check fuse F4 in the engine compartment. If the build date is after March 2004 let us know and we can provide further info.

It would simplfy things if you add the vehicle model to your signature. That ay it would always come up.

 

Try checking the connector, it could have a wee bit of verdigris in it.

 

hi thanks for the replies, its an 08 plate 2.2 diesel x type

 

Fuse F14 30A in passenger fuse box. If that is ok then try the relay that supplies it.

 

ive taken the relay out and tested it with battery and multimeter and thats fine also the fuse is fine, the heated mirrors work fine but still nothing at the heated rear window, doing my brain in now

 

The next thing is to check the connector at the window to see if you are getting power to it. If you are then the window is probably faulty if not, then you may have a wiring issue.

 

And don't forget to check the ground connection does just that!

 

had the panel off the rear above the seats and found the wiring to the window, it has a block connector with a blue and a blue/red wire, do we know which is the live and negative? ealy summer i had an idiot in a stretch limo drive into me and it was damage to rear passenger door and quarter panel, i'm wondering if one of the wires where pinched

 

Nice to see language being exercised

 

I think you've found the Blue and Red/Blue wiring to the rear park assist speaker that is located under the parcel shelf. The wire you're looking for is a Green/Blue one that is behind the trim on the rear window pillar. The ground wire is a Black wire under the other side pillar trim.
If you haven't got DAB radio, don't get mixed up with the radio aerial wiring that is a co-ax cable plus a Yellow/Green wire that powers the aerial module behind the lefthand trim panel.

Don't forget the engine has to be running to get power to the rear screen heater.

 

no the wires are on a white plastic connector that pushes onto a metal male spade type connector that is built directly onto the heater pattern of the back window and is situated behind the airbag cover above your left ear when sitting in the rear passenger side seat

 

just thinking out loud here i wonder if when the car was repaired someone may have replaced the cables wrongly, i know that the rears interior was partially stripped while they replaced the rear wing so gonna have a look this morning to see if i possibly have a green / blue wire pushed onto somewhere else

 

well hopefully job done, haven't tested it yet because i was struggling to reach up to the connectors but it appears that the spanner monkeys who mended my car just shoved any wire they could onto the connector, i stripped out the rear carpets seats airbag covers parcel shelf cover lifted and was extremely fed up as couldn't find anything looking out of place but as i was putting everything back together i noticed a small black wire with a molded black spade connector on it tucked behind the wiring loom, i took the airbag panel off the drivers side and the cable looks exactly the same as this one so i attached it. my car didn't have reversing sensors as standard so the blue and blue/red are obviously spare wires for that option. i wouldn't have found the problem without this site as i wouldn't have known that the connector was wrong so big big thanks to everyone