P38 No Heated Rear Screen

Hi

My heated screen doesnt work at all....probably hasnt since I purchased the car in August....nor does heated mirrors.

The LH window works - so Im assuming its not simply the fuse as below

12 30A Heated rear screen and LH rear window.

Any other suggestions what to check next..... with the cold weather coming Id like to get it fixed.

Cheers

Gary

Have you checked the wire loom going into top tailgate. As for the heated mirrors i dont know but is there a difference between heated and non heated mirror glasses. I know that there is on a ford and the heated ones are more expensive so possible they may have been broken and replaced with standatd

Have you checked the relay in the fuse box. Think it is the 3rd or 4th one down on the outside row. It is clearly marked on the fuse box lid. Take it out and check for voltage. If you have that then test the relay by swapping it with one of the other yellow ones (try the one from the front heated windscreen which is the relay next to it.)

Hi

I have looked in engine bay fuse compartment - I cannot find a relay that is for heated rear screen. There are 2 for heated front screen (R & L).

Can you specificy which R number is the relay for rear screen ??

I have removed the tailgate panel where the wiring comes in through the rubber boot, however I cannot see how you actually access the wiring in the tail gate section and where it actually connects to heated rear screen element. Any suggestions or pics ??

Cheers

G

ngary said:

Hi

I have looked in engine bay fuse compartment - I cannot find a relay that is for heated rear screen. There are 2 for heated front screen (R & L).

Can you specificy which R number is the relay for rear screen ??

I have removed the tailgate panel where the wiring comes in through the rubber boot, however I cannot see how you actually access the wiring in the tail gate section and where it actually connects to heated rear screen element. Any suggestions or pics ??

Cheers

G

Click to expand...

Just checked on mine and you are correct. Sorry for the bum steer. I have just looked at the wiring manual on RAVE (see attached) and it does not look like there is a relay for the rear screen.

Hi

Thanks for checking - thats what stumped me - normally there is a relay for rear screen somwhere...

So are the likely problems

1. Wiring to heated screen being damaged - but unsure how to access it
2. Faulty switch on hevac unit

assuming fuses are OK.....?

Cheers

G

ngary said:

Hi

Thanks for checking - thats what stumped me - normally there is a relay for rear screen somwhere...

So are the likely problems

1. Wiring to heated screen being damaged - but unsure how to access it
2. Faulty switch on hevac unit

assuming fuses are OK.....?

Cheers

G

Click to expand...

Not looked at mine but can you get behind the headlining and see if can find the wire. failing that get mulitmeter and turn heated screen on and probe the tag on the elenent and an earth. if get voltage then it the elements. You can get repair stuff for them. Cant remenber where from but it usualy advertised in practical classics. Mine dont work either, bus i drive vans all day i dont look out rear screen anyway

ngary said:

Hi

I have looked in engine bay fuse compartment - I cannot find a relay that is for heated rear screen. There are 2 for heated front screen (R & L).

Can you specificy which R number is the relay for rear screen ??

I have removed the tailgate panel where the wiring comes in through the rubber boot, however I cannot see how you actually access the wiring in the tail gate section and where it actually connects to heated rear screen element. Any suggestions or pics ??

Cheers

G

Click to expand...

IIRC the relay for the rear screen heater is in the BECM itself.

Hi

Does that mean that the BECM (??) nees to be replaced or can I replace the faulty relay within the becm unit ??

Cheers

G

ngary said:

Hi

Does that mean that the BECM (??) nees to be replaced or can I replace the faulty relay within the becm unit ??

Cheers

G

Click to expand...

First look in RAVE to check that the relay is in the BECM and which one it is. You should be able to test the signal going into the BECM and the signal coming out before you think of taking it to bits. If you can prove the signal goes into the BECM but does not come out, Then you can think about opening up the BECM to replace the relay and check for corrsion etc. It's just as likely that the HEVAC is not sending the signal to the BECM.

Hi

The connections to the BECM are outlined at Demystifying the BeCM

C324 connector at from of BECM is accessed by removing the fuse cover, the phillips screw and the front / side panel pullout connectors. One the shroud is removed you can see the front of the BECM.

The Rear screen output (?) wire is purple and green (connectore 324). I checked for voltage at this wire, with rear screen switch on/off and found it was aorking - so Hevac switch is working.

I removed the tail gate top cover (4 phillips) and the rubber and pulled (gently!) the headlining down at the point where the wiring goes into the tailgate.

I fished out the wiring and found a double connector with a purple / green and black wire. I checked the voltage at this connection and found it was activated by rear screen switch.

I tried measuring voltage at various points along the actual screen relative to an earth - but no voltage.

My conclusion so far - power to tailgate connector - but not getting to actual screen.

Can anyone tell me how to find where the power / earth actually connects to the rear screen elements ?????

Cheers

Gary

Next step...

From inside of upper tail gate remove the phillips screws on the plastic cover of the high level brake light. Gently pry away...

The side panle on the upper tailgate you need to get to is the driver side...gently pry away from body. About half way up is the connection to the rear screen element. It has a Purple/green wire and connects to a double metal connection that should be connected..... thats where mine has the problem. Power all the way down to this point...but the connection has actually come of the rear screen itself.

Not sure how to put this back on the screen element - advice ???

Cheers


G