Central Locking problem. Looking for DIY solution.

[BadBanshee]

Got a problem with my central locking: When I want to lock the car I have to lean over to the passenger door and press the lock before I get out, then press the lock on my remote.

When I press unlock on my remote, all the doors unlock. However, when I press lock on my remote, only the driver's door and boot lid lock but not the passenger door.

Obviously the central locking is working somewhat because the passenger door unlocks but it doesn't lock for some reason.

I'm wondering how I would go about diagnosing the problem? Is it likely to be something that needs replacing or just fixing into place again like a switch that has been turned off somewhere? Also where would I be looking to try and fix the problem? I was thinking of taking the door panels off on the passenger side to get to the lock mechanism.

Thanks in advance.

[Mr AJ]

Probably not a solution in your case but my focus did a similiar thing when we was out shopping, Had to lock the passenger door manually or the entire central locking circuit would just lock then unlock itself straight away.

Was at the end of a particularly stressful day so i booted the door (It's already covered in dents anyway!) resulting in a barage of "What the fk did you do that for you fking idiot blah blah blah" from the Mrs - Which only worsened when i tried to lock on the fob again and it locked fine first time and has been good ever since!.

Have you tried taking the door cards off and having a poke around inside? Everytime my CL has failed its been something stupid like a control cable slipping off a solenoid*. Edit: Re-reading the post no you havent! So take the door panels off and have a look!

*Disclaimer: I am in no way mechanically minded and may be using the wrong words to describe this. I just tend to hit things and fiddle with them until it works or breaks beyond repair, As demonstrated above.

[miniman]

I would guess at the solenoid, which is indeed inside the door and looks like this:



Tip: arm yourself with some replacement door card clips as I find it virtually impossible to remove them without breaking them. http://www.ebay.co.uk/itm/DOOR-CARD-PANEL-TRIM-CLI...

[Codswallop]

Have you tried the first rule of fixing anything?

Turn it off, and then on again. By which I mean, lock all the doors/ the car, and disconnect the battery. Leave for 10-15 minutes, and reconnect (make sure you have the radio code etc beforehand).

It fixed my central locking when it got out of sync on an old Ford at least :shrug:

[BadBanshee]

Codswallop said:

Have you tried the first rule of fixing anything?

Turn it off, and then on again. By which I mean, lock all the doors/ the car, and disconnect the battery. Leave for 10-15 minutes, and reconnect (make sure you have the radio code etc beforehand).

It fixed my central locking when it got out of sync on an old Ford at least :shrug:

I got the battery changed recently, not to fix this problem, but because it was flat anyway. Funnily enough, though, that fixed my fuel gauge.

[BadBanshee]

miniman said:

I would guess at the solenoid, which is indeed inside the door and looks like this:



Tip: arm yourself with some replacement door card clips as I find it virtually impossible to remove them without breaking them. http://www.ebay.co.uk/itm/DOOR-CARD-PANEL-TRIM-CLI...

How would I know if the solenoid has stopped working?

[BadBanshee]

Mr AJ said:

Probably not a solution in your case but my focus did a similiar thing when we was out shopping, Had to lock the passenger door manually or the entire central locking circuit would just lock then unlock itself straight away.

Was at the end of a particularly stressful day so i booted the door (It's already covered in dents anyway!) resulting in a barage of "What the fk did you do that for you fking idiot blah blah blah" from the Mrs - Which only worsened when i tried to lock on the fob again and it locked fine first time and has been good ever since!.

Have you tried taking the door cards off and having a poke around inside? Everytime my CL has failed its been something stupid like a control cable slipping off a solenoid*. Edit: Re-reading the post no you havent! So take the door panels off and have a look!

*Disclaimer: I am in no way mechanically minded and may be using the wrong words to describe this. I just tend to hit things and fiddle with them until it works or breaks beyond repair, As demonstrated above.

I thought that technique only worked on old TVs!

[GreigM]

BadBanshee said:

How would I know if the solenoid has stopped working?

the door would stop locking - common symptom of solenoid failure....

[Krikkit]

Miniman has hit on it - replace the solenoid in the door, see if that sorts it. If not it's a wiring problem.

[BadBanshee]

GreigM said:

the door would stop locking - common symptom of solenoid failure....

And even if the door DOES unlock with the remote, the solenoid could still be faulty?

[miniman]

BadBanshee said:

GreigM said:

the door would stop locking - common symptom of solenoid failure....

And even if the door DOES unlock with the remote, the solenoid could still be faulty?

As the door unlocks, there is clearly power to the solenoid, ruling out relays, fuses, severed wiring etc.

The solenoid uses an electromagnet to move the actuating rods in the door - up and down or side to side - you'd need to have a look inside the door. If you want to diagnose it, you should be able to use a power probe to fire 12v onto the solenoid terminals. You might find it is as simple as a connecting rod coming loose, but this seems unlikely as it consistently opens the lock - if the connecting rods were broken, I'd be surprised if it would keep doing this.

A cheap way to diagnose it - swap over the solenoid from the driver's door.

[BadBanshee]

Is it an easy job swapping over the solenoids? And what am I looking for if I do this?

Just seems odd that the central locking works perfectly in one sense (unlocking) but not in another. Obviously there's something different controlling the locking to the unlocking. And I'm guessing the solenoid is for both, so that should be fine.

[Krikkit]

Not necessarily - the action for opening the lock is a bit easier than closing it. As far as replacement goes, grab a Haynes manual, everything's covered in there. Not too bad a job, but it is a bit fiddly inside the door.

[GreigM]

BadBanshee said:

Is it an easy job swapping over the solenoids? And what am I looking for if I do this?

Just seems odd that the central locking works perfectly in one sense (unlocking) but not in another. Obviously there's something different controlling the locking to the unlocking. And I'm guessing the solenoid is for both, so that should be fine.

There will be 2 control signals to the solenoid, it may not be receiving it in one direction. Even if its receiving it then it could be an electrical fault controlling that direction.

It could also just be sticking - take off the door card and spray with WD40 while locking and unlocking.

[BadBanshee]

Krikkit said:

Not necessarily - the action for opening the lock is a bit easier than closing it. As far as replacement goes, grab a Haynes manual, everything's covered in there. Not too bad a job, but it is a bit fiddly inside the door.

Haynes manual faultfinder tells me "latch locks but will not unlock or unlocks but will not lock" could be either faulty master switch, broken or disconnected latch operating rods or levers, faulty relay, or faulty control unit.

It then refers me to chapters in the book where I can find those things. But the information regarding them are for removal and refitting of said components. No information about actually diagnosing the components. I might have a poke (if I can find my screwdriver. I have precision screwdrivers, will that work?) but it'll probably just be like looking at a bowl of spaghetti to me. I'll take some pictures at least.

[Snowboy]

This happened on mine a while back.

The solenoid had a wire tbat went to the lock, thevwere was attached to a hook and the hook was broken.
The solenoid could push the lock to unlock but not pull to lock.


Five minutes with some tape and wire and it was working good as new.

[BadBanshee]

I'm hoping for the bit of tape solution so bad lol. My precision torx screwdriver unscrewed the door panel but the arm rest has bigger torx screws so I'm on the hunt to expand my toolkit.

doogz, me saying I want to be a mechanic falsely suggests I'm an amateur at the moment. But I'm still at that stage where I think cars are magic

[avocado]

BadBanshee said:

I have precision screwdrivers, will that work?)

You'll need a proper set of screwdrivers.

[Krikkit]

A good set of Torx bits is very much needed if you want to disassemble these cars. I have a set that fit sockets and some nifty allen-key type ones (words fail me) that are great for taking interior bits off.

[Captain Muppet]

BadBanshee said:

Krikkit said:

Not necessarily - the action for opening the lock is a bit easier than closing it. As far as replacement goes, grab a Haynes manual, everything's covered in there. Not too bad a job, but it is a bit fiddly inside the door.

Haynes manual faultfinder tells me "latch locks but will not unlock or unlocks but will not lock" could be either faulty master switch, broken or disconnected latch operating rods or levers, faulty relay, or faulty control unit.

It then refers me to chapters in the book where I can find those things. But the information regarding them are for removal and refitting of said components. No information about actually diagnosing the components. I might have a poke (if I can find my screwdriver. I have precision screwdrivers, will that work?) but it'll probably just be like looking at a bowl of spaghetti to me. I'll take some pictures at least.

Once you have the door card off look, at the bits inside the door when you press the central locking button to lock and then unlock the door. Maybe take the driver's door to bits too, to see how a working one works.

If a linkage is stuck, broken or wonky you should be able to see it trying to work and how to fix it.

If nothing happens at all try swapping the solenoid on the driver's side. If that works then it's the solenoid that's duff.

If nothing happens after this it's wiring, and that's all magic to me (so I'd get a multimeter out and try chasing the wiring until I find out it's the bit of wiring that goes through the door as this bit tends to wear out first, or a corroded connector somewhere).