Do you know your car's MoT and mileage history? Our user profiles will show you for FREE | No thanks
01 2.2HDi Door lock mechanism. - machika
Had an interesting experience with our C5 today and I wondered if anyone else had encountered anything similar.

For some weeks we have had a problem with the near side front door locking mechanism. The door wouldn't unlock with the remote control but would unlock with the key. At first it was an intermittent problem but then it wouldn't work at all. It had been like this for three weeks at least and today it was taken to the local Citroen dealership, to undergo a diagnostic check to identify the problem.

They reported that no fault could be identified and the door was unlocking with the remote control. Is it possible that the diagnostic check equipment cured the problem? The remote control definitely wasn't unlocking the door yesterday.

Edited by Webmaster on 06/02/2010 at 13:51

Citroen C5. Door lock mechanism. - Mondaywoe
I have never had any problems with my locks, but have heard of some owners getting them replaced under warranty. At one point, however, my dealer asked for both sets of keys so that they could be re-programmed as part of a software update. Perhaps they have done that (although you'd think they would have said) On my old Xantia I sometimes found that the central locking wouldn't work if one of the doors wasn't quite closed properly. It might have been the same thing here. Remember that the C5 also has automatic locking on the boot above a certain speed and it won't unlock until a door has been opened. Perhaps the boot wasn't quite latched.

Multiplexing can cause odd faults - C5 occasionaly has 'ghosts' in the system which disappear of their own free will!

There again, of course, your plip could have had a temporary glitch (loose battery?) or maybe the battery is getting abit low???

Citroen C5. Door lock mechanism. - machika
This problem only affected the one door. It locked ok, but wouldn't unlock with the remote control. All of the other doors did and the boot. As I said, the problem persisted until yesterday.
Citroen C5. Door lock mechanism. - machika
Can you believe it, the door is now acting up again. It unlocks with the remote control sometimes and sometimes it doesn't.
Citroen C5. Door lock mechanism. - Mondaywoe
No, this certainly sounds more like a door-specific fault - wiring, actuator etc. I'd just take it back to the dealer and tell them there is definitely a fault - albeit intermittent.The warranty will cover it.

I'm pretty sure other owners have reported having the lock motors (solonoids?)changed. I suppose there must be some sort of switch that is actuated by physically turning the key - this would appear to be delivering current to the actuator, whereas the plip sensor isn't. Maybe it's just a loose connection.

Oh - just watch the dealer doesn't make a mess of removing / refitting the door lining. You could land up with a working door lock and a lot of nasty marks!

Citroen C5. Door lock mechanism. - machika
Oh - just watch the dealer doesn't make a mess of
removing / refitting the door lining. You could land up with
a working door lock and a lot of nasty marks!

That's what worries me. It happened when we had our Xantia repaired. The door wasn't damaged but had to be sprayed to blend in with the paintwork on the new wing and the mess they made of putting back the trim, door seals, etc., had to be seen to be believed.

It may be better to put up with the inconvenience of having to use a key.

Secondly, we don't have a Citroen warranty on this car, as it was invalidated by the previous owner. Our warranty doesn't cover main dealer labour rates.
Citroen C5. Door lock mechanism. - Mondaywoe
I know this is a bit nosey and completely off the point of the door locks, but I'd be fascinated to know how the previous owner invalidated the warranty! Presumeably he tinkered where he shouldn't have......

Citroen C5. Door lock mechanism. - Ben with a Genesis
The C5 boot doesnt lock above a certain speed, it just won't unlock!

The boot lock is electric and uses a motor to unlock.

Slamming it locks it again. I am sure that slamming it with the battery disconnected locks the boot. Still not sure how to lock the doors with the battery disconnected though.

Citroen C5. Door lock mechanism. - Civic8
Unless I am mistaken central locking has a control unit.unless fault is found in this unit.drive/solenoid on that door will be the prob.diagnostics wont cure the prob.control unit cannot control a faulty solenoid they tend to when operated return to lock position.replacing is usual cure but as I dont know the car is only a suggestion.hope it helps.?
Citroen C5. Door lock mechanism. - Mikec5
Hi Machika,

Not sure if you ever got this sorted by my c5 has just started to do this - The drivers door will not unlock on remote, will on key and locks on remote !

Did the dealer fix it.

Citroen C5. Door lock mechanism. - Kerdevan
Hi, I have had similar problems which seemed to start with putting the rear seats down. I suspect that an electrical harness travels under the rear seats and the spare wheel. It started with the rear hatch door unlocking and has now spread to the front passengar door and the rear offside door. I think the multiplex wiring is the central cause for all of the problems but as yet I have no evidence.
Citroen C5. Door lock mechanism. - jrdriver
My car has started locking by itself everytime I shut the driver side door. Any ideas??

Ask Honest John

Value my car

Amount to borrow
Sorry. The minimum loan amount is £1000
To pay back over

My credit score

Best available rate 9.20%

Total repayment £9,304.93

Total cost of credit £1,804.93


60 monthly payments

Apply now

Representative example

The Representative APR is 13.2% (fixed) so if you borrow £7,500 over 4 years at a rate of 13.2% p.a (fixed) you will repay £199.21 per month and repay £9562.20 in total.