New comfort module yes or no?

O

oddbod907

New Member
Oddbod 907 Hi all i am new to A2OC
I am have problems with my 1.4 petrol A2 2002 1,27000 miles only stared a few days ago and appreciate any help i need to know if i need a new ccu and i have seen one with 2 keys but will this module be ok with my A2 that has electric heated seats air con and 2 electric front windows mine still works all the central locking but clicks when the key is turned and the interior lights on the drivers side doors don't light up but do when the key is removed from the ignition ie it does not see the drivers door or drivers rear open on the dash display but both windows still work and fobs lock all doors and alarm led lights
 
Hi,
the interior light / dashboard display not illuminating is a symptom of a faulty door open micro switch (or door switch wiring break).
This is relativly common and is usually a broken solder joint in the lock circuit board although this microswitch itself can sometimes wear (or disintigrate!) depending on level of use.
The clicking of the locks is also a symptom of a fault with micro switch(es) inside the lock mechanism that detect when it is locked and unlocked. This is normally a broken solder joint and can be fixed by re soldering. The extra clicks are done intentionally to make sure that the doors are unlocked as the car can't tell if the doors are locked or unlocked because of the faulty switch.

In either case you will need to remove and repair or replace the affected locks. Your CCU won't be the cause of this issue.

Its easy to tell which door open switch or switches are faulty as you just need to open each door and see if the light comes on. To tell which lock or lock switches are faulty you will need to have the fault codes read as that will tell you which lock is not working properly. Its not easily possibly to tell otherwise.

warm regards

Andrew
 
For reference, pictures of the lock module:

The door open switch is external, see coloured wires.

48281


Its held in place by a clip:

48282


The "button" activates the switch.

48283


Inside, the lock motor switches and the wiring connector socket are soldered to a PCB. These joints on the PCB can break and require re-soldering.

48284


Lock motor switches.

48285
 
There are two separate faults described in the original post.

The clicking caused by the faulty lock module motor switches can be ignored if the doors lock and unlock OK. The only symptom will be the extra clicking and faults logged in the CCU memory.

The interior light not coming on is a different thing as there are a number of implications to this.
If its the driver's door that doesn't work then the fuel flap release button won't activate when the door is open, as the car thinks the door is closed all the time.
Also, if the door switches, particularly the driver's don't work, the alarm doesn't know that the car has been entered after being unlocked. The car will re-lock and re-arm the alarm if the car thinks that the doors have been left closed after a short while. It is then possible to unlock the car and get in and have the car re-lock and the alarm go off with the driver sitting behind the wheel! Turning the ignition on cancels the alarm, but only if its done quick enough.
 
A switch fault can be caused by two reasons, the solder joints on the lock PCB and / or the wiring. Although failure of the PCB joints is quite common, if the door has been opened and closed a large number of times, the bending of the wire as the door moves can eventually cause it to fail.

The lock modules are a bit of pain to remove as due to the limited space inside the door, the window frame has to be taken out. Thus its worth verifying that the wiring is OK before removing the lock module.

In the front doors, the lock modules are always connected to the "door controller" which is the electronics attached to the electric window motor. The back doors are the same if they have electric windows or all the lock module wires are routed to the body of the car and connected directly to the CCU with manual windows.

If the interior light doesn't come on when the door is opened its worth checking the wiring by unplugging the lock motor connector and shorting the door contact switch pins. If the light comes on, the wiring is fine and the lock module is faulty. If the light doesn't come on, the wiring is faulty.

Door lock module:
Contact switch: pin 4 purple/yellow
Switch common: pin 8 brown
 
Last edited:
You must log in or register to reply here.
Back
Top