Central locking

[neilrenault]

Hi. I've a '96 plate bongo which central locking has now completely failed. Originally the passenger front door was spasming (very loud continuous noise), and sometimes unlocking itself. It was only cured by removing the fuse. Now its stopped working completely. I've tried...

- Checked fuse 1 and 4 (top row), all fine
- all door looms are fine and been replaced 1 year ago

Would this suggest its the central locking relay rather than an actuator or solenoid as none of the locks now work and was it just on its way out hence the spasms ? If so is there an easy way to identify which is the relay behind the glove box ? (see image) - https://imgur.com/a/yeTKrR1

[mikeonb4c]

I dont have a photo of it but my problem turned out to be that relay (i THINK it was grey in colour and very on view and v quick to swap over once you remove the glovebox cover). I got a 2nd hand replacement from Bongospares (£20 i think). I had already paid a lot more to fit a new drivers side door loom....which didnt fix it......doh!

[g8dhe]

Difficult to be sure it might be that a fault in the front door lock solenoid/motor has caused the relay to be damaged.

[neilrenault]

Thanks both. Indeed I wondered if they were linked. I've bought a new relay now as that might bring the system back to life. If the passenger lock shows signs of malfunction again i'll remove the fuse and look to replace the lock too. I inquired about a replacement locking mechanism (before i learnt of the relay through your forum) but they needed to know if a 3 or 5 wires. I've had the door panel off but guess i need to completely remove the lock and unclick the door lock mechanisms to see the wiring at a certain point?

[g8dhe]

Its a two wire locking system, all three doors (passenger, sliding & rear) are driven from the same signals in parallel;

So if none work suspect the module, if one door gives problems suspect the motorised door lock, see here https://www.youtube.com/watch?v=X4i2eO1CA24

[neilrenault]

Hi, so I replaced the relay module and unfortunately the other locks (passenger, side and rear) still don't work. Have re-checked the two top row fuses and they are still fine. The side door does the automatic closure but guess the circuit for that is different to the central locking. Any any idea of other points of investigation? thanks.

[g8dhe]

If you have a meter it might be worth checking the loom running from the module to all three locks and that there is power and signals to the module.