Drivers door lock.

[Billy_rfc]

Hey guys, I'm having some problems with the drivers door wanting to open when Im driving which came as a bloody fright the first time it did it!
Need to know how best to get into the lock so I can check the cables etc? will I have to take out the rear seat?

Billy.

[whatever]

I don't know about that, but a common cause of the doors opening used to be misplaced/maladjusted or missing magnet parts on the door frame. It's how the car "knows" that the doors are closed.


There must be quite a bit in the archives about this.

[mike_e]

Is it a mechanical or electrical problem? Does the door just fly open or can you hear the solendoid working before the door opens?

I would suspect it's mechanical as the system should prevent actuation of the solenoid when the car is moving.

Check that the lock mechanism isn't all gummed up and works freely, you should be able to operate it by hand to test it. Make sure it will latch and stay latched. If so I would suspect the door plate needs adjusting inwards slightly.

[Bezrek]

I've got the same problem.... My drivers door keeps popping open on my 1996 4.2 Cerb. The window doesn't come down as with the normal opening procedure. If anyone can help I'd be most grateful.

[RR Cerbera]

I've had this on both of my Cerberas. If the window isn't going down then it's most likely a mechanical issue and can be solved by adjusting the door catch/striker.

You may be unlucky and just have a catch that has gone weak for which there is no solution but a new catch.

[flashheart]

I may be barking up the wrong tree here but I thought there was a speed sensor in the ECU gubbins that prevented the doors from opening above 5mph?? If the speed is sensed as greater than this any signal from the door proximity sensor (ie misadjusted magnet) should be overidden?

[bezrek]

I suspected a mechanical problem and therefore did some very basic fault finding. The catch seems to have two distictive positions. The first semi-locks and with a reasonable amount of pressure can be forced open. The second position is well and truely locked. I closed the door and gave it a good push from inside (the trim didn't like this too much) and the door doesn't budge. I'm therefore looking at an electrical problem I guess?

[Billy_rfc]

This is an old post this one!

What I found to be the problem with my car was that the actuator that operates the locking mechanism was sticking so not allowing the lever on the lock to sit in the correct position and thus allowing the lock to release the door at anytime it wanted.

Cured this with a new actuator which wasn't expensive (was a ford bit) which I did myself.

Billy.

[Bezrek]

Just had a long trip out to Nuneaton and the damn door is possessed! It seems speed related though. At 60 it happens occasionally but 70+ it wants to be open more than it is shut. Something is triggering the door lock mechanism to open because it is definitely locked tight up until it pops open.

[mike_e]

The door solenoids (or the interior buttons) should be disabled when the car is moving. Test this by trying to open the door when the car is moving, using both interior and exterior buttons. If they open at any speed then you clearly have a problem with the speed sensor signal. That said, the door still shouldn't operate randomly, it's a safety feature.

If the door motors are definately operating at speed then perhaps you have a dodgy door switch. Interesting that it seems to get worse at speed, might be worth poking around inside the drivers mirror and the door wiring. Also check the wiring/onnectors on the door control box.

[bezrek]

Mike e, I'll have a good poke around this Sat to see what I can find. I want to get it sorted by Sunday so I don't let the side down during London Thunder. I've got an idea about how to get into the door itself but is there a trick to looking inside the mirror unit?

[simonkd]

My drivers door opens onto its catch (neither open or closed) at about 150mph. I put it down to the fact that the door vibrates quite a bit at this speed unless both windows are open at least half way when it doesn't do it. Might it be something to do with airflows? It's something I've put up with from day one but I treat it as a safety feature that prevents me doing these speeds in the rain.

Regards
Simon

[Billy_rfc]

Bezrek said:

Something is triggering the door lock mechanism to open because it is definitely locked tight up until it pops open.

Can you hear the door actuator operating when the door opens? You know, the sound thats made when you press the button to open the door normaly? If not then It aint getting operated electrically.
My door would shut as normal and then at any time would just open and found it to be as said before, the actuator not allowing the latch to return to the correct position.
Have a look behind the panel in the back of the car where the seat belt is located and see if the actuator is extending properly.

Billy.

[Bezrek]

OK... progress at last. Billy_rfc I think I have something very similar to what you described. At first I thought the door mech was holding things tight but now after some more advanced fault finding (pressing the door harder and at the very rear edge) I find it will spring open. I did some speed trials and at an (X)Mph the door opened but with both the passengers and drivers window open I had no door troubles at(X+Y)Mph(where Y = a lot). Now all I have to do is either find out if the actuator is not returning the mechanism all the way or where to get a new lock on the cheap! Sorry for any confusion caused and thanks to all who helped out.

[Billy_rfc]

The actuator is a Ford bit and I think it was £10 to £20. The door lock itself is a Vauxhall part with mods (badly welded on bits!) as to connect up to the actuator and emergency handles.

Billy.

[Billy_rfc]

The actuator is a Ford bit and I think it was £10 to £20. The door lock itself is a Vauxhall part with mods (badly welded on bits!) as to connect up to the actuator and emergency handles.

Billy.

[Bezrek]

Ok... I think I've sorted the door issue. The actuator and manual release cables had been set with too much pressure on the release mech. This was causing the latch to remain partially open. I've now reset the pressure and so far no more random door openings. Once again thanks to those helpers out there.