Volvo S60 t5 boot opening and wiring problem

[Bigsi15]

Hi guys

I have a 2002 Volvo S60 which has developed an annoying problem with the boot not being able to be opened with the handle switch, only the key fob or the key.
At the moment when the engine is turned off the only way I can open the boot is either mechanically with the key or using the boot opening function of the key fob. The handle switch does absolutely nothing. When I turn the ignition on or off this triggers the boot to open and if I try and use the handle switch with the engine running it blows the fuse to the rear light clusters and the numberplate lights but does open the boot most times.

Today I had a probe with a multimeter on the resistance setting testing it on the wires that lead from the handle, from the lock mechanism itself, and up from the wirejoint that runs behind the left light clusters out of the bodywork into the boot lid, to see if any of the wires were broken.

All of the wires and connections showed resistance on the meter in the same way as a piece of new speaker wire does (so I assume are patent), except for a small brown and blue wire which runs from inside the boot of the car up to the first joint in the boot lid where the wire splits to the lock and the handle, which showed no resistance.

Because of this I am assuming that maybe this wire has a break? However I bridged it with a piece of new speaker wire which then showed a resistance on the meter but did not solve the problem.

I have changed the latch mechanism giving the same problem as before, and tested the switch in the handle using the meter which shows resistance when it is depressed and held.

I don't know enough about car wiring to go any further and am at my wits end now so would greatly appreciate any help!

Thanks very much!

[Bigsi15]

Ok read the codes today and have a few...

Upper electronic module
Uem-0004 siren communication fault

Rear electronic module
Rem-6f51 tail gate handle signal too low

Climate control module
Ccm-001f air quality sensor signal too high

Driver door module
Ddm-0025 mirror motor signal missing

nk most are fairly meaningless and I think I have a problem with the climate control occasionally blowing hot air out of one vent and cold out the other centre vent but interestingly it mentions the tail gate handle signal being low...

Any ideas what this means in the real world?!

[mike 850]

The tailgate handle signal looks like it's the culprit, that's probably the wire that's broken, I'm not sure but as its all canbus signals maybe speaker wire might not allow the right signal through? Defo sounds like that brown and blue wire, I wonder how easy it would be to strip the covers to find the break, you may find others wires shorting or something so bypassing won't fix it?

[Bigsi15]

Good question! And good point Thanks for your help, I think I might start by replacing the entire structure of wire from within the boot to the boot lid and see if that solves the problem rather than go hunting at this stage as knowing my luck I will cut another wire by accident Or make a mess of the current one and be even more stuck!

Do you know if that brown and blue wire is indeed the wire which powers the handle?

Thanks again

[mike 850]

Are your number plate lights working, Haynes looks like brown/blue wire is for them. Rear handle says the wires are brown/red and blue/black. I suspect then you have more than one break or a short?

[Bigsi15]

Yes strangely they work fine (unless the ignition is on in which case the handle shorts the lights and right side rear lights), it's odd how the ignition being on then let's it work but seems to overload it. I think your probably on the money with a short somewhere

[Harvey]

Yes strangely they work fine (unless the ignition is on in which case the handle shorts the lights and right side rear lights), it's odd how the ignition being on then let's it work but seems to overload it. I think your probably on the money with a short somewhere

But the number plate lights are on .Then ,the harness does it have just the one plug or more at the rear module.

[Harvey]

http://www.volvowiringdiagrams.com/v...20Diagrams.pdf

[Harvey]

[Bigsi15]

Hi Harvey thanks for your replies especially the diagram, that could prove to be very useful locating which wire colour does what!
Not sure about the numbers of plugs at the other end though

Thanks again
Si

[Bigsi15]

Harvey I have had another look at the wiring and I see your point now, the blue brown wire with no resistance is supposed to be the one that supplies the numberplate lights according to the diagram however as you say they work which makes it odd as that wire shows no resistance. Once the group of leads goes into the boot there is a plastic connection and it goes further in and joins a number of other wires into the Rem or whatever the black fuse box is

[Dancake]

Can you open the boot remotely using the key fob when the car is locked?

[Bigsi15]

hi there, yes I believe so

[Dancake]

The handle switch itself is connected to the number plate lights. You can't just buy it seperately, and it costs around £100 or more from Volvo. Easy enough to change. If it's opening ok with the key and the fob, then the wiring to and from the boot lock must be fine. I'd be looking at the handle itself to make sure it's receiving voltage, that the negative cable is ok, and that it has continuity when the button is pressed.

[Bigsi15]

Yes the handle seems to complete the circuit and show resistance when held closed so I'm assuming it works, I got another secondhand one and both do the same thing. I'm waiting on a new section of wire that runs from the boot to the boot lead to see if that makes any difference but if it doesn't then I'm totally out of ideas

[Bigsi15]

Think it's sorted, replaced the wire from the boot to the boot lid and seems to work! Hope this helps someone Thanks for all your help guys!