Central locking again.

[paulwitchard]

The recent acquisition has an odd central locking problem, any advice on where to look gratefully received as electrical problems not really my speciality.
Its a 1992 turbo diesel, LHD, has got a plip which does nothing apart from the little red light coming on.
When all the doors are locked, opening the drivers door with the key will unlock them all.
Using the key in the drivers door only locks the drivers door and does not activate any of the other door solenoids.
Using the key in the passenger door does nothing to the central locking system.

[RxBX]

The recent acquisition has an odd central locking problem, any advice on where to look gratefully received as electrical problems not really my speciality.
..................................
Using the key in the passenger door does nothing to the central locking system

Hi Paul,
This is normal for UK (RHD) with central locking with a plip controller, so I would imagine the same applies for (LHD) car's. So the passenger side door will only open that door with the key and nothing else !

However BX's fitted with NO plip controller/function but which do have central locking operated by the key only, should open or close the whole car which ever door side lock is being used to open or close the vehicle !

I see you have other BX's in your stock list !
So what I suggest is to check the central locking controller unit with another one from your other BX's (Provided they have central locking) which are working normally as these can and do sometime fail due to dry soldered joints on the PCB within the black box !

On the MK2 BX's the access to the black (Oblong) box is very simple and quick.
Basically all you have to do is lever out carefully the square trinket panel/dish (For the rear passenger's) at the rear of the handbrake console.
When this panel/dish has been removed look inside the cavity and fish out the central locking black box unit.
Unplug the unit and swap over with another one from a known working vehicle and test/check to see if the central locking unit works (hopefully) ?

If the central locking now works correctly/hopefully that's it !

All you need then is a good spare, if you cannot source a good second-hand one in Normandy, then PM me as I should have a good one available.

Also if the central locking work's correctly but only with the key, check the the plip by operating the IR beam/direction into a digital camera to see if a beam is showing up on the camera screen, hopefully it does if not the battery maybe nearly exhausted (Although you did state the Red light showed up upon pressing the plip button) but the IR beam still needs to be checked out !

If the IR beam is showing up on the camera screen next check is to see if there's actually a roof receiver fitted and correctly plugged in (This is fitted into the overhead map light console just under black domed cover in the middle of the lights) as you never know if some-one has removed/messed with the roof receiver as you stated that you've just recently acquired the vehicle !

I hope this maybe of help and please report back with your finding's ?




RxBX

[docchevron]

most of what /\ he said, but, I'd start by pulling the bellows from the A pillar to the door, whip the door card off and check the trigger wires from the solonoid back into the loom. It's fairly common for them to break with age.

Next up, and whilst you're in there, disconnect the control rod off the dolonoid and manually move the lever the rod attaches to on the lock, is it nice and smooth, free to move, not at all stiff?
If it is stiff to move, then give it a dose of WD40 or some such and work the thing about till it's free, it wont be the issue in this case I shouldn't think, but it wont hurt as you're in there already..

If you have a spare solonoid try that, it's only held in with 2 8MM bolts, and at this stage I'd say it sounds very much like the wiring to the trigger side of the solonoid, or the solonoid itself.

[paulwitchard]

Well its definitely not the central locking controller unit - swapped them over and it made no difference - worked perfectly on the 'old' car, but not at all on the 'new' one.
Will have to get into the door next - but after tomorrow's CT it might be going down the list a bit!

[Vanny]

Central locking controllers have never failed according to my stock of 20+ of the stupid things.

My bet is either a break in the wiring harness from car to door, or a faulty microswitch in the bottom of the driver door lock solenoid.

Failing that, does it have an after market alarm?


In the case of the plip not functioning, you can test the plip is actually transmitting by pressing the button while looking at the diode in the end through a digital camera. If it is transmitting, you will see it flashing white. Also handy for checking tv remotes!

If it's transmitting then you can check the module in the roof is correctly plugged in and with no signs of corrosion, and after that you can check that the plip and control module are actually coded to each other. There are instructions online for doing this.

[RxBX]

Central locking controllers have never failed according to my stock of 20+ of the stupid things..............

You must have been/are lucky then I've had at least two that failed on BX's I've owned in the past plus I've supplied/repaired several for other BX owner's too !

...................................
In the case of the plip not functioning, you can test the plip is actually transmitting by pressing the button while looking at the diode in the end through a digital camera. If it is transmitting, you will see it flashing white. Also handy for checking tv remotes!............

Thar's already ben covered in posts /\

.......................and
after that you can check that the plip and control module are actually coded to each other. There are instructions online for doing this.

Here's a LINK !



RxBX

[KevR]

I should have some spare solenoids lurking if you want to try one of those.

How did the CT go...?

[paulwitchard]

Might take you up on that sometime...........
CT - a longish list but nothing terminal........handbrake, indicators and brake lights, I think its something to do with the mass of wires behind the left hand rear light, they were working perfectly yesterday , rear silencer leaking - but there was another good previously enjoyed one in the boot, 3 tyres (effectively 4), and one I am not sure about 'demi train AV (y compris ancrages):jeu important ou anormal rotule et / ou articulation (infd) - presumably play in a steering joint or the column?
Otherwise the usual list of leaks and dents!!

As far as the plip is concerned I'm not bothered about that, I'm a key man rather than a plipper!!

[KevR]

The 'demi train avant' refers to the wishbones, ball joints and track rod ends as far as I know. Play in the lower ball joint's the most likely culprit as they don't last long, especially on rural roads. Right hand one's the most likely as they get the most grief (in France - opposite in UK of course). Actually, just re-read it and the 'infd' stands for inferieur droite - lower right. So that's your culprit (maybe also arm bushes). New ones are peanuts (although if you can get a genuine Cit one it'll last a lot longer). Sometimes easy to fremove the old ones, sometimes a bit of a pig. I've got the appropriate castellated socket, but half the time I've always had to hammer seven shades of something or other out of them to the get the old one out, and only use the socket for putting the new one in.

Legende Assurances got back to me last week, finally. For the MX-5, the white BX, a 2CV, the tractor, two mopeds and the Ducati it comes to about 350 euros a year. Unfortunately too late now to change the H van over as well this year as the contract's already started again.

[Defender110]

Play in the lower ball joint's the most likely culprit as they don't last long,

Well I never knew play in the lower ball joint would affect my central locking??

[KevR]

It's chaos theory... you know, a butterfly beats its wings in Brazil and there's an earthquake in China, that sort of thing...

[Defender110]

[Vanny]

Central locking controllers have never failed according to my stock of 20+ of the stupid things..............

You must have been/are lucky then I've had at least two that failed on BX's I've owned in the past plus I've supplied/repaired several for other BX owner's too !

Out of interest, how many of these have had alarms with remote cetral locking fitted? From a component side they are well over specced and i assume the only reason for failure would be water ingress, or electrical abuse.

...................................
In the case of the plip not functioning, you can test the plip is actually transmitting by pressing the button while looking at the diode in the end through a digital camera. If it is transmitting, you will see it flashing white. Also handy for checking tv remotes!............

Thar's already ben covered in posts /\

Right you are, missed it while skimming the epic saga.

Here's a LINK !
RxBX

My hero, i can NEVER find the link when i need it. Will go write it down!

[paulwitchard]

Finally got round to doing something about this as the car has now passed the CT.
Doc's bang on the money - 2 identical green wires broken off, and several others on the point of failing.
As there is not a lot of space to put in some sort of couplers, any suggestion as to where the next set of connectors are under the dash, before I start having a poke about. Working on the principle it might be easier to rejoin the wires up in a more spacious environment!

[KevR]

I think they go from the door, through the A-post and into the cabin, down to the floor, under the carpet in the footwell and there's a connector under the seat somewhere. I'd be inclined to pull some new bits of wire through, and connect somewhere inside the door and somewhere between the A post and footwell.

This is something I need to check soon as although my central locking works ok normally (no alarm/plip), it's taken to occasionally locking itself, especially when it's wet, so I assume some kind of short circuit.