2002 S60 Doors do not unlock from Master switch

quietcoolone · Post by **quietcoolone** » 27 Dec 2014, 08:50

Hello Everyone,
Just picked up a used 2002 S60 for my daughter and among other needed repairs, there is a door lock issue i can't yet figure out.
Vida says CEM-6A02 Door unlocked, right rear signal too high.
I don't have a remote key, but the key i have will lock/unlock all doors/trunk from drivers door lock cylinder. The master lock/unlock button on the drivers door locks ALL doors but does not unlock any door. The only way to unlock is to pull up on the individual door lock knob.
I have checked the unlock relays on the fuse console in trunk (drivers side) and tested with those from my 04 S60 (same part number), but still no joy.
While pressing the master lock/unlock button (with doors already locked), there is click sound coming from all 4 door locks (as if they are getting signal), but for some reason they won't unlock.
Any ideas why the key lock/unlock all doors but master lock button is able to lock but not unlock any of them?
Thanks in advance.

rerobin66 · Post by **rerobin66** » 27 Dec 2014, 10:27

I know on my s80 they have a reset process. and I just bought an s60 and I think it does as well. While sitting in the car with all doors closed lock all doors then pull up on drivers lock. lock it again with power button then try and unlock with power button. If this sequence does not work try variations of manual locking and unlocking or vice versa using the power button. Hope something works for you, without a remote key somethings can't seem to work.

Integrity · Post by **Integrity** » 27 Dec 2014, 12:50

You at one point say "the key i have will lock/unlock all doors/trunk from drivers door lock cylinder"

Then you also say "The only way to unlock is to pull up on the individual door lock knob".

The last remark combined with the 6A02 dtc leads me to believe you need a right rear door latch....

rerobin is correct about reset procedure, but you would have automatically done that by cycling key in drivers door... thats how we reset them at dealership at pre delivery...

A faulty rear latch is notorious for confusing your master lock button function, The master lock switch is part of the DDM and sends its lock/unlock request to the CEM... CEM gets the rear latch signal from the REM all through CAN network voltage signals. DDM says hey CEM I need you to unlock all doors CEM askes REM to perform function through the relay, REM says hey CEM I got an open signal in R/R I ain't gonna do it. Frustrated the CEM posts your 6A02 dtc and the DDM is left scratching it's head.

quietcoolone · Post by **quietcoolone** » 28 Dec 2014, 16:05

Integrity wrote: A faulty rear latch is notorious for confusing your master lock button function.

integrity you were spot on.== thank you so much.
I went to a local auto recycle and pulled the Rear Passenger Door lock from a 2001 V70. Installed it in the S60 and the master lock/unlock switch is now working.
Note the part number on my lock was 8650557 and that of the V70 was 9141708.
Now i need to tackle the surging idle situation (cleaned ETM already but the engine runs with a surging idle).

Once again big thanks for the help.