Central Locking Failure - About to run out of Petrol!

[Aubs]

Yesterday when I tried to unlock my car, instead of being greeted with an open door, I just got a small whinging sound. The alarm works fine, and I can open the doors manually with the key, so I didn't deem this to be an urgent problem.

Unfortunately the petrol filler cap is also on the central locking system. I realised this 30 minutes ago in tesco petrol forecourt.

Now being fairly ignorant about central locking systems, I have made a number of assumptions here. I suspect that there is an individual motor controlling each lock, and that there is a module which sends a driver voltage to each of them to faciliate the locking and unlocking.

Now as none of the doors unlock/lock, this seems unlikely to be a fault with all of the motors, so I would guess that the control module is on it's way out and is no longer able to supply the current required by all the motors.

Does this make sense? Have I made it all up?

If it does make sense then where is the module located, and who has a replacement?

[DanThe]

Have you done the Red/Black wire mod?
The fuel filler flap can be undone by pulling the boot carpet back and moving the actuator rod by hand

[town325i]

if the red black wire mod does not work i have a working central locking module

[Aubs]

Hi Dan, I've searched for the red/black wire mod but brought up nothing. What does it involve?

[DHFiS]

http://www.e30zone.net/e30zonewiki/inde ... g_problems

[pac1982]

http://www.e30zone.net/e30zonewiki/inde ... g_problems

Thats not the proper red black mod i followed that guide only to have the system fail on me again a few days later thankfully Mr Moore came to the rescue and got he problem sorted for me, i'll see if i can dig up my old post

[Aubs]

Thanks for the link, i'll try that tomorrow.

This afternoon i'm just going to go for moving the actuator - i pulled the boot lining back on the right hand side, and the only interesting thing I can see is a white case, mounted maybe 300mm back from the filler cap, it has a power feed.

Am I on the right lines here?

*UPDATE*

Bit of groping around behind the actuator had me sorted!

@ Pac1982: If you could find that link buddy it would be much appreciated

[daimlerman]

Red/black wire mod may or may not help the OP!
Remove the speaker cover in the driver's foot well and have a look at the wiring harness that runs to the driver's door.
Red/black wire is always 'live',it enters the drivers door to feed a heated door lock that is rarely fitted to UK spec cars.As a result,it tends to corrode on the 'A'pillar socket pins.Proper cure is to locate the two red/black wires on the car side of the socket,cut them free and join'em together,thus enliminating the trip through the 'A' pillar socket.
I think that in the OP's case,the 'thermal' link in the central locking control module has blown.
This module hides in the driver's footwell below the speaker,held by a couple of bolts.There is a better guide to removing and fixing in the zone wiki.

[pac1982]

This is the post i made when i was trying to fix my locking............

http://www.e30zone.net/modules.php?name ... ht=locking