CCM and central locking question

[Brudder]

Hi. I'm having problems with the rear door on 2003 passat estate. It won't open by any means. I have got the trim, armour and window out of the door to get to the lock. Firstly does anyone know if there is a way to release the rear door lock so i can open the door, and secondly has anyone got tips on fault finding to see if the problem lies with the lock, wiring or Convenience control unit. I have had water in the passenger footwell, but I have never found water within the CCU box and it looks in very good condition as well as the wiring. I have a VAG code reader, but it comes up with "link error" when trying to access the central locking category ( it does work with other categories, but not all)

Regards

Ben Rudder

[martin1810]

Have you unwrapped the wires to the ccm. The damage is usually out of sight, especially at soldered joints and earth connections. A registered copy of vag-com should read ccm and indicate if the lock has lost power or if it has lost communication. Have you managed to get lock cover off so that you can "encourage" the levers.

[Brudder]

Hi Thanks for your reply. I don't have proper vag-com, i have a sealey code reader that is for VAG. When you say about the lock cover, could you give me more info please. When you talk about encouraging levers, do you mean the interior door opening cable. I have read that soldering in the door lock electrics can fail, but it seems you can't open the door to get to the studs to get the lock out of the door for inspection.

Ben

[Brudder]

Hi. I decided to use my sealey code reader again, and discovered a CAN gateway option and this brought up the code info:

"Door control module rear right (J398)

Static - no communication".

Does this narrow it down to the lock or could it still be the CCM

regards

Ben Rudder

[martin1810]

The fact that it says no communication suggests a damaged ccm wire but it could be a damaged lock. On the b5 there isn't true communication between the ccm and the rear doors like there is with the front doors. I would check your ccm wires again but you may still have to strip the door.

[Brudder]

Thanks

Done some more work on it today, and I've realised that I triggered the door module code. I have the door taken apart so that I can get to the lock. I didn't realise that the plug going into the electric window winder needed to be connected for the door lock to operate. After reconnecting this, when i erased the code it didn't come back. The strange thing is, is that now i have all the door armour off, I can see that the motor is actually working and the door lock rod moves when the keyfob is activated. I still can't open the door from inside or out even though the dead lock seems to be removed???

regards

Ben

[martin1810]

It's probably the dead locking that's keeping it shut.. Try a couple of sharp tugs with everything disconnected.