Xc90 2005 check brake lights

[Ams]

Hi

My xc90 2005 reg has just come up with check brake lights message. The middle brake light on the top of the boot lid works but the two side one do not.
I have read a few posts about the same problem for other models. Other posts have mentioned it could be a break light relay in the cargo compartment. But on my 2005 model, I don't seem to have relays of any sort next to the fuses..the ones hidden further in do not look like brake relay. Can anyone please point me in the right direction...im a complete novice. By the way. .brake light bulbs are not blown.
Many thanks
Ams

[john langrick]

GR-258323.jpg does this help? This is 2005 rem, the units on the lower level are relays

[Ams]

Hi John

Thanks for your reply. Just to confirm, is this in the cargo? Because I cannot see it. And neither the manual nor Haynes explains the part number or Location of the relay too. Thanks

[4x4]

Try this link... Click

[Ams]

Originally Posted by 4x4

Try this link... Click

Originally Posted by 4x4

Try this link... Click

Hi..thanks for this. Unfortunately this is not how my box looks. My one is a little newer than that model. I'm trying to upload a photo but can't seem to attach the one I want to.

Screenshot_2018-12-22-20-45-21.jpg

Screenshot_2018-12-22-20-43-42.jpg

[john langrick]

Understand your frustration.. Mine is 03 my xc90. It does appear the rem changed a few times. The YouTube link is from a pre 2006 model, but certainly USA by the look.

The rem on my earlier post is supposed to be from a my 2005, will look and see if it is the same as mine in the morning and post a pic.

But the principle for removal is the same and the post I mention earlier does have a description on how to get full access.

Another idea is if you look at eBay and enter xc90 rem, there are lists there, post a link to the closest, this may help. But note this module seems to change year to year.

The trick will be to identify the relay. I did this more by trial and error, but that being said, the relay was the only blue one. Beware that if it has been changed in the past, the new switch may have been black. You should still be able to swap there relays around as I did and this process indicated the faulty relay.

Let me know if a pic of mine will be helpful.

John l

[Ams]

Originally Posted by john langrick

Understand your frustration.. Mine is 03 my xc90. It does appear the rem changed a few times. The YouTube link is from a pre 2006 model, but certainly USA by the look.

The rem on my earlier post is supposed to be from a my 2005, will look and see if it is the same as mine in the morning and post a pic.

But the principle for removal is the same and the post I mention earlier does have a description on how to get full access.

Another idea is if you look at eBay and enter xc90 rem, there are lists there, post a link to the closest, this may help. But note this module seems to change year to year.

The trick will be to identify the relay. I did this more by trial and error, but that being said, the relay was the only blue one. Beware that if it has been changed in the past, the new switch may have been black. You should still be able to swap there relays around as I did and this process indicated the faulty relay.

Let me know if a pic of mine will be helpful.

John l

Hi John

Here is a link to what my REM looks like.

https://www.ebay.co.uk/itm/Volvo-XC9...AAAOSwAclboi7d

Dare I say it, I can't seem to find anything that looks like a brake relay.

Again, any help appreciated.

Thanks
A

[Clan]

Originally Posted by Ams

Hi

My xc90 2005 reg has just come up with check brake lights message. The middle brake light on the top of the boot lid works but the two side one do not.
I have read a few posts about the same problem for other models. Other posts have mentioned it could be a break light relay in the cargo compartment. But on my 2005 model, I don't seem to have relays of any sort next to the fuses..the ones hidden further in do not look like brake relay. Can anyone please point me in the right direction...im a complete novice. By the way. .brake light bulbs are not blown.
Many thanks
Ams

There are no relays from 2005 it is fully electronic …

The REM plays no part in the 2 outer stop lights the current simply uses it as a junction box it goes in one connector and out of another …

Fuse F9 in the CEM feeds the stop light switch


what you need to check is whether the voltage is going into the REM and coming out of the REM

It goes in plug A, pin 18 ( Green with a yellow stripe wire )
and out at plug B, pin 3 ( yellow wire) the wire is green with a yellow stripe …


Best do those tests first


You might find water getting in the CEM on that model , anyway see what is happening at the rear first ...

[SwissXC90]

Clan you beat me to it!

For the Brake Circuit
Left hand taillamp and right hand taillamp are wired directly to the REM, both landing on pin B:3 on the REM, both with a yellow wire.

Then the REM goes from pin A:19 green/yellow to the CEM pin A:15

The REM also connects to the center brake lamp from pin F:4 with a white wire.

Check output of the CEM.
Check input to REM
Check output from REM

Unfortunately all are a bit awkward to get to.

[Clan]

Originally Posted by SwissXC90

Caln you beat me to it!

For the Brake Circuit
Left hand taillamp and right hand taillamp are wired directly to the REM, both landing on pin B:3 on the REM, both with a yellow wire.

Then the REM goes from pin A:19 green/yellow to the CEM pin A:15

The REM also connects to the center brake lamp from pin F:4 with a white wire.

Check output of the CEM.
Check input to REM
Check output from REM

Unfortunately all are a bit awkward to get to.

The centre stop light and main stop lights are on two separate circuits for safety so if one fails the other will still work , The Centre stop light signal is sent from the CEM to the REM on the network , so the REM does the switching .. the outer bulbs are controlled direct by the CEM at the front