S60 Electrics: Heated mirrors, No heat ???

[111]

Have posted this before and this may be a long shot but, The mirrors (both) on my s60 se do not get warm when switched on. I have now found that there is no power to the heat pads, the electric movement is fine (I realise this is not the same power feed as to the pads) & so is the heated rear screen but there is nothing at the connectors in the mirror. They have not worked for the 7 months I have had the car. Any ideas would be appreciated.

[s60ben]

Heater Elements are Fubared then

[BobS]

Elements might be ok as 111 said there was no power to them?

Try the fuses or I am sure there will be a relay somewhere. Check that. But you will need to look at a wiring diagram.

Bob

[craig8661]

if its like my 940 are they combined with the rear demist on the one switch what mine do is heat the mirrors for 5 mins then turns mirrors of then carries on with rear window you could have a faulty relay

[D5 Monkey]

Originally Posted by craig8661

if its like my 940 are they combined with the rear demist on the one switch what mine do is heat the mirrors for 5 mins then turns mirrors of then carries on with rear window you could have a faulty relay

As Craig says, I also think that there may be a function inbuilt where they only switch on when the outside temp is below 1'C? may be imagining this but I'm sure I've either been told this on here or read it in the owner manual.

So are you sure that when it's icy outside at 6am tomorrow morning when you switch on both front and back demisters, your wing mirrors don't come on?

[s60ben]

Originally Posted by BobS

Elements might be ok as 111 said there was no power to them?

Try the fuses or I am sure there will be a relay somewhere. Check that. But you will need to look at a wiring diagram.

Bob

So he did...

The door mirror heating takes the following path

Button >Wire> CCM >Canbus> CEM >Canbus> DM/PDM

For the demist to work, the engine must be running

The heated mirrors are deactivated 12 minutes after they have been switched on by the CEM sending a signal over the Canbus to the DDM/PDM modules.

Fuse 27 15Amp (AFAIK dependent on MY year/chassis) is the fuse that looks after this, but as you've said your power windows/mirrors work ok then it must be ok because it also looks after that!


There are no relays involved in the operation of the heated mirrors, nor are the "temperature dependent" - I've checked on the Volvo wiring diagrams I have

111 you have a pm

You can check the following:

Check for oxidisation/high resistance connections on the control module and power door mirrors.

If it's 10 pin connector, check between door control module #11B and power door mirror terminal #5 for intermittent short to supply/ground or open circuit

If it's a 16 pin connector, check between door control module #11B and power door mirror terminal #8 for intermittent short to supply/ground or open circuit

There are diagnostics within the PDM/DDM for heated mirrors you just need to find someone to read the codes....... however, it would appear that all the diagnostics involve looking for shorts/open circuits.

Should be fairly easy to diagnose/fix tbh

[Chris_Rogers]

As has been said this is not a straight forward fuse / switch / relay circuit.

Have you checked the mirror heaters for continuity?

It may be the system will not apply power to the mirrors unless a continuous circuit exists.

Other than that it seems there may be a configuration issue with the CAN system.

[111]

Thanks for all the replies (help). The power to the heaters was checked as was the heater part of the mirror with an AVO or something like that. Thanks Ben I got your pm & have replied. As I said there is no problem with any of the other elec equipment on the car. I will have a look at the wiring diagram to see if I can work it out. May take a while as I am no electrician.

"Button >Wire> CCM >Canbus> CEM >Canbus> DM/PDM" What ????

[s60ben]

Originally Posted by 111

Thanks for all the replies (help). The power to the heaters was checked as was the heater part of the mirror with an AVO or something like that. Thanks Ben I got your pm & have replied. As I said there is no problem with any of the other elec equipment on the car. I will have a look at the wiring diagram to see if I can work it out. May take a while as I am no electrician.

"Button >Wire> CCM >Canbus> CEM >Canbus> DM/PDM" What ????

LOL, welcome to the wonderful world of TLA's

Fog light button
Connects to by straight wire
Climate Control Module
which connects by the Canbus network (how the car communicates)
to the Central Electronic Module
Which connects to (via Canbus network)
The DDM (Driver Door Module) & PDM (Passenger Door Module)
which then connects/powers (by straight wire)
to the respective sides heated mirrors

You should have email

[Viper_7]

Originally Posted by s60ben

The heated mirrors are deactivated 12 minutes after they have been switched on by the CEM sending a signal over the Canbus to the DDM/PDM modules.

Thought it was 3 mins for the mirrors then 10 for the rear.

Reset of the CEM may be in order.


Never actually stated but is the rear demister working?