No heating rearwindow!

RH480 · Post by **RH480** » Sat Jan 17, 2004 9:36 pm

I have no heating rearwindow anymore.
No power to the heatingthreads, no indicatorlight in dash either.
However, if i hold the switch "in", the "beep" for indicating heated rearwindow always on, function as supposed to.
The fuse is OK.
Is there a relay for the heated rearwindow, in the relaybox in the engine compartment??
Or is the relay hidden in the CEM

Anyone???

RH.

strangegame · Post by **strangegame** » Sat Jan 17, 2004 9:54 pm

what about the switch itself - that may be faulty
i know it still works (bleep) but still. it may be faulty

RH480 · Post by **RH480** » Sat Jan 17, 2004 10:09 pm

strangegame wrote:what about the switch itself - that may be faulty
i know it still works (bleep) but still. it may be faulty

Thanx, will check the switch tomorrow with my multimeter to see if it works correctly.

RH

red480gt · Post by **red480gt** » Sat Jan 17, 2004 10:50 pm

Hi

The relay is built into the CEM. There are two fuses to check, are both OK?

the switch turns on the CEM relay, so if your getting a beep then your switch is fine, its more likely to be the second fuse of a bad connection.

(The dash lamp is on the second fuse num 19)

I had alot of trouble on both my 480's on the tailgate wiring as the wires bare nd short out because they are moved all the time, check your wires whre they come from the car to the tailgate

hope this helps.

chriskay · Post by **chriskay** » Sun Jan 18, 2004 11:58 pm

Yes, Red; the wiring at the tailgate is favourite in my opinion too.

volvofox · Post by **volvofox** » Mon Jan 19, 2004 5:31 am

Hmmm.
My experience is that the CEM plug (the rear one on top of my "88 old version of CEM) is mostly burned melted and gray. Its possible the beep still works, but the output connectors are bad.

Look at the CEM. its on the base of the A pillar , behind the plastic and upwards, on the passengers side for you "wrong" side driving uk's

Its kind of a hassle to find and remove the CEM box the first time. Donot swap it with the Engine Control Unit, its on the exact same place, on the other side.

RH480 · Post by **RH480** » Tue Jan 20, 2004 9:10 am

red480gt wrote:Hi

The relay is built into the CEM. There are two fuses to check, are both OK?

the switch turns on the CEM relay, so if your getting a beep then your switch is fine, its more likely to be the second fuse of a bad connection.

(The dash lamp is on the second fuse num 19)

I had alot of trouble on both my 480's on the tailgate wiring as the wires bare nd short out because they are moved all the time, check your wires whre they come from the car to the tailgate

hope this helps.

Ok, so there is two fuses for the rearwindow heating?
Was not aware of that, will check this, btw, the switch is OK!

wedge69 · Post by **wedge69** » Tue Jan 20, 2004 11:02 am

The situation you describe is the same as mine - no light on dash board, no heated rear window, but still a beep if you hold down the switch for a while.

Here is what I was told by my garage - In the CEM, one of the connections had burnt out that controlled the heated rear window. They took the CEM out and cleaned up the connection, but couldn't gurantee that it wouldn't go again. Two weeks later it broke....

keithemm · Post by **keithemm** » Tue Jan 20, 2004 4:56 pm

if it makes you feel any better, i have no beep, no heated rear windscreen, and no light in the dash-and both fuses are ok. perhaps it is the switch, but i'm a very new newbie to all this, so i have never taken one of those switches off before.

David Thornber · Post by **David Thornber** » Tue Jan 20, 2004 7:53 pm

Mine had no beep and nothing worked, fault was wiring burned out at CEM connector, and plug slightly melted in vicinity of the two heavy rear window wires.

I think I have some pictures on an old PC of how I repaired mine, took about 2 hours. If interested I will have a look and post them.

Briefly, I cut the socket connector inside the CEM

, cut both wires to the plug. and effectively bypassed the multi pin plug for these two wires, by soldering cable directly to the CEM circuit board and joining to the previously cut cables on the main loom.

Result: working rear window!!

Don't try this though if you are not 100% sure what you are doing, otherwise you may totally kill the CEM.

keithemm · Post by **keithemm** » Tue Jan 20, 2004 8:12 pm

those pictures might be quite useful..never had the CEM out myself, might be quite fun. How disastrous would it be if i killed the CEM? hmm, i guess it does control all the lights and everything. I have an extra relay fitted on mine for the indicators, an auto-electrician did it for me. i think i have some major problems with it, as when i disconnect the battery, then reconnect it, then turn the ignition, it beeps, which i believe is part of it's system check. If it beeps, then there is an eror.

chris1roll · Post by **chris1roll** » Tue Jan 20, 2004 8:27 pm

if it beeps when you turn on the ign, then maybe it has been left connected for the self test mode?
see teh FAQ on the club site for how to set the test mode up. if the two wires are still connected this could be where your problem lies.... just a thought.

David Thornber · Post by **David Thornber** » Tue Jan 20, 2004 8:34 pm

I'll have a look for the pics tomorrow. The beeps when you turn the ignition on aren't the series of 5 or 6 that are supposed to remind you to put the seatbelt on are they? Try putting belt on before turning ignition on and see if it still happens.

keithemm · Post by **keithemm** » Tue Jan 20, 2004 8:54 pm

if the two wires are still connected this could be where your problem lies.... just a thought.

I haven't actually had the CEM out before, so the wires shouldn't be connected.

The beeps when you turn the ignition on aren't the series of 5 or 6 that are supposed to remind you to put the seatbelt on are they?

It's a long continuous beep.

As part of the ever expanding mystery of my 480 electrical faults, my interior courtesy lights don't usually come on when i open the door, although when i disconnect, then reconnect the battery, they do. That is, until i turn the ignition. That is also when i hear the long beeeep.

Keith

chris1roll · Post by **chris1roll** » Tue Jan 20, 2004 9:07 pm

keithemm wrote:I haven't actually had the CEM out before, so the wires shouldn't be connected.

You may not have done, but some previous owner might!

You would be amazed the things you find on second hand cars. My sisters new car had the cem held in with sticky foam pads, instead of the proper screws. and one of the headlights in my old 240 was held in place with a piece of wood!

keithemm · Post by **keithemm** » Tue Jan 20, 2004 9:13 pm

wood? wow. you could be right actually, i might go about the unveiling of the little black box. An auto-electrician has had it out before though, would he have spotted it do you reckon?

chris1roll · Post by **chris1roll** » Tue Jan 20, 2004 9:22 pm

depends how au-fait he was with the 480's electrical system. it wouldn't seem out of place, if you see what i mean. And i wouldn't have thought he would randomly disconnect wires unless he _knew_ they shouldn't be. or someone could have seen it and gone " oh, they should be connected" and hooked them up.

This is all largely conjecture - it may not be that, I was just thinking about it when you said it beeps like that. mine is quiet apart from :

indicating,
Holding down the window heater switch,
Doing the self test.
think thats it.

keithemm · Post by **keithemm** » Tue Jan 20, 2004 9:27 pm

Right, my CEM is coming out tomorrow...poor 480 may never work again. Does anyone have a photo of the circuit board, and where the wires would be?

chris1roll · Post by **chris1roll** » Tue Jan 20, 2004 9:35 pm

EDIT: d'oh thats not the url.... its all under the FAQ at the club site: volvo 480 link above^^^^

also remove the glovebox, you won't get anywhere near the top screws otherwise.
It is a tight fit, there is a knack to getting it out.

the self test wires are under teh glovebox, or down behind the kick panel(where teh bonnet release is.)there is a black "hatch" on the lower surface of the dash, on my new car teh wires are immediately above it. I think this is probably where they are supposed to be, for ease of access, but they get moved around over time.

My 480 is unsullied!!

(apart from the clockhouse, which someone had overtightened all the screws so it disintegrated

) so then i had to use the housing out my old car and the guts out my new one. that took a while.

keithemm · Post by **keithemm** » Tue Jan 20, 2004 9:40 pm

I just took a peek at your 2 volvo websites, seems you're a bit of a veteran when it comes to tinkering with these babies. I don't suppose you wanna come and fix mine for me? would be a good project

I may well give this a try tomorrow, actually maybe not, i need it in the evening. My glovebox sorta falls off anyway, the front anyway, missing some hinge pins. The instructions make it sounds so simple.