[waddy]

Hi there - I have a 53, 2003 L322 Vogue. For some reason the heated rear screen is not working. The button works, the light comes on, all the fuses and relay are fine. Does anyone know where the control module is located for this? I have had the access panel off to the tailgate and 2 black wires go to a grey box - is this the control module? There is power going to it constantly on 2 wires with a third that is seemingly dead. This module looks like it is something to do with the phone/aerial as it has an antenna link to it also.

I assume these two wires are the only pick-ups to the screen?

Ive had this problem since I bought the car a year ago and it's getting on my nerves now - especially with the ice and a wet dog in the back breathing heavily after a days shooting!!

Cheers

Mark.

 

[waddy]

Anyone?

 

[Dan_UK_1984]

First of all you need to download the Rave Workshop Manual. A search should yield enough results and hopefully help you get to the bottom of your problem. Secondly I've never had a problem with steaming up as long as the air con is left on, being climate control it is designed to be on all of the time so that it can de-humidify the air, otherwise electrical gremilns will start to apear.

 

[GKP]

If it's been such a bother for over a year, why don't you take it to a dealer?
This isn't something I'd normally suggest, but your post infers that you aren't that experienced when it comes to wielding a spanner on a car. It would be all too easy for you to damage something expensive by your present trial and error method.

 

[waddy]

The climate isn't on as there is a crack in the low pressure pipe. I've stripped this out and am awaiting some more wire for the tig welder so I can re-seam the pipe (I am pretty experienced when it comes to cars and spanners - having stripped down and rebuilt more than a few cars, diggers and tractors in my time!!). I find it a little insulting that someone presumes I am not 'handy' with a spanner or i am resulting to trial and error methods at the drop of a hat!

When icy the front heated screen does what a heated screen should do - melts the ice. The rear does not - this doesnt seem correct (even with the climate off?!)

The RAVE manual indicates the control unit, relay and fuses for the rear screen but only indicates 2 wires when there is a third going to the unit in question.

 

[Dan_UK_1984]

I find it a little insulting that someone presumes I am not 'handy' with a spanner or i am resulting to trial and error methods at the drop of a hat!

Unfortunately a lot of the people that come on here and ask questions without introducing themselves are completely mechanically illiterate and I'm sure that no offence was intended at all.

Everything is controlled from the HEVAC ECU, read the "Description & Operation" section in Rave. It says that the HEVAC ECU energises the Relay on the Rear fuse panel, so have you checked this relay?

Leave the bits connected to the screen alone, unless a connection is broken to the screen its going to be system related I would have thought.

The dealer may actually be the best bet - they can query the HEVAC ECU to figure out what's going on, it may be reporting back a reason why it cant turn it on.

Dan

 

[waddy]

Thanks, Dan.

I should have introduced myself really. My apologies for that! No offence taken. The relay is working and the fuses are live. I assumed (rightly or wrongly) that the issue may lie with the grey box I spoke of. It has got to go back to a service centre for the gearbox (which has just been replaced) in the new year so I'll get them to check - although they did carry out an initial inspection when I asked them about it whilst it was in and drew a blank - although I think they only checked the basics as i have.

Cheers

Mark.

 

[Dan_UK_1984]

It has got to go back to a service centre for the gearbox (which has just been replaced) in the new year so I'll get them to check

Are they an actual LR dealer? They will need the correct equipment to interigate the ECU propperly. Sometimes you can save yourself a lot of hastle by going to the stealer when things arent working, other times they will just rinse you for all your cash! It's difficult to know when do go! The trouble with the Hevcac ECU is it's massively complicated and there are so many sensors involved that will stop other things from working.

 

[Dan_UK_1984]

The wiring diagram doesnt mention your small grey box :?

[attachment=0:3q59wbze]Rear Screen.jpg[/attachment:3q59wbze]

 

[waddy]

That's what confused me. I've got that diagram from the RAVE manual but cant trace what the box is? The two wires to the heating element come from this box?

I'll take a photo later and upload to see if anyone can shed some light as it's stumped me! Unless what I have got is somethinf to do with the Radio/Phone reception and the heater elements are powered elsewhere on the screen (i.e. not at the top?) but I can't see where.

Cheers

Mark.

 

[waddy]

Got it!

The screen wiring is at the other end of the tailgate! I took off the side trims and bottom trim to reveal the screen wiring. A plug which wasn't connected was the culprit all along!

Cheers

Mark.