ZX Central Locking Problem

Post by **Rhothgar** » 25 Sep 2011, 13:50

Another job that I started yesterday was trying to trace a fault on the central locking.

I am almost totally imcompetent when it comes to diagnosis of electrical problems.

I have read a few posts this morning to help me try and resolve this latest issue.

The plip does not work on the car and I am not worried about that at the moment. When the car is locked with the key on the OSF, I can see the locks moving even though they do not do anything.

I stripped out both off-side door panels yesterday. Sylv usually has to open the OSR door by getting her key under button and forcing it up. I can't do it so there is a knack to it - that's how stiff it is!

On actuating the front door button rod yesterday, I could feel power to the solenoid but if I continued then power was lost.

It almost sounds like a wiring break which I will check out today.

I noticed in one of the posts though that it is a good idea to clean the block connectors of the solenoids using switch cleaner and also that if the system works using the 'other' door then it is the 'other' door lock which is the problem.

Also, went on Ebay and a few people are selling solenoids on there which have TWO connectors to them. Sylv's only seem to have ONE though.

So I assume a block connector may have come loose and fallen off?

I would really appreciate some advice on this!

I'm off to Maplins now to get swtich cleaner and silicone spray.

spider · Post by **spider** » 25 Sep 2011, 16:05

I would guess its the same as the 306's , the wires break in the door looms. The 'loom' is part of the car not the door unfortunately, they did not take the opportunity to 'move' this to make it easier to repair when they changed shape slightly.

Also they'll cut out for a few seconds to a minute if overloaded, remove the lock buttons if possible so there's just the rods there, then try it. A stuck button can cause something similar to what you have described too.

Post by **Rhothgar** » 25 Sep 2011, 20:28

Ey up, Andy.

Hope you're leeping well.

Cheers for your input.

I've had the OSF to pieces again and still none the wiser.

Cleaned the connector between door and A-post with electrical switch cleaner, pulled the rubber back and had a tacet look around. All seems good.

Popped off all the door buttons to relieve any load from them.

When I push the solenoid down, it tries to move ALL the other doors so the wiring must be OK or am I wrong?

When I pull on the solenoid, there is no action from any of the other doors.

Checked the voltages at the various connectors on the OSF.

Got 11.4 volts from the blue wire and 0V from Orange wire.

Brown block connector to solenoid. 0 Volts to both grey wires.

White block connector to solenoid. 0.1V to both orange wires and 0V to blue wires.

Does this give anyone any clue as to what may be wrong, if anything?

Tried to get a BoL from Halfords today only to find that they sent them all back to Haynes last week as the car is classed obsolete!! Still managed to pick up one for my 1959 Land Rover though!!!

Xantidote · Post by **Xantidote** » 25 Sep 2011, 20:50

You can pick up a new or used Xantia Manual on eBay - should find plenty of choice. I bought a used one locally a year ago for about £3.99

Post by **Rhothgar** » 29 Oct 2011, 09:27

Need to re-ignite this post as I am now back on with this job!

Got a Haynes manual for Sylv's ZX and the wiring diagrams are interesting to say the least! Does anyone know if the connectors are actually marked with the numbers shown on the diagrams?

The codes on 703 (Driver's Door Locking Motor) are 3B1, 3B2, 3B3 and 2M1, 2M2. I seem to remember that there was a two connector to the solenoid, one with 3 wires and one with 2 wires.

Does anyone know if this is how these are coded? E.g. 3B1 means 3 wire connector, B for white colour (although I believe it was brown) and 1 for wire number one.

Having a clear understanding of this coding would allow me to start to decipher the wiring diagram.

Any knowledge / experience on this would be greatly appreciated.

Post by **Rhothgar** » 30 Nov 2011, 22:24

Anyone? It's unusual not to get any feedback!

Norlander · Post by **Norlander** » 30 Nov 2011, 23:36

Fwiw, we had years of ongoing but intermittent problems with central locking on our ZX....
Locks (all or any) would even occasionally go off and on while driving along smooth motorway stretches.
Behaved itself since in summer, though -- the hatch finally refused to lock at all, so we got a replacement lock for it at a scapyard.
Now have to have an additional key on our keyrings just for the boot, but worth it since all works ok so far.

Post by **Rhothgar** » 30 Nov 2011, 23:53

Cheers Norlander. They do seem temperamental to say the least.

I really need some sage advice regarding my previous post on codings on wiring diagrams. One day... Just one day... I will understand them!

citronut · Post by **citronut** » 01 Dec 2011, 08:16

the codeing is usualy just coloured indicators on on the wire were it/they terminate, and quite offten its just one short stripe along the wire, but not all the way around,

as Andy says check all the wires in the rubber truncking in the door shuts,
as one or more broken/fractured wire in there can cause all kinds of funny goings on,

if you find any broken wires in the door shut, make sure you add a length of wire into the repair, so you can push any couplings/crimps into the door piller,

otherwise if the repaired section is within the gap between door and piller they will continualy break again,

regards malcolm

Post by **Rhothgar** » 01 Dec 2011, 21:36

Hi Malcom

Hope you're keeping well.

Thanks for the response. All wires have been checked previously. They're VERY difficult to gain proper access to as I remember.

Post by **Rhothgar** » 10 Apr 2012, 19:41

I have taken all the door buttons out to ease the load on the system.

When the key is turned in the driver's door lock, I can feel the metal rod on the OSR door move down. However, it does not move enough to physically lock the door.

When I press the button down from inside it locks the door.

I have stripped out the OSR door lock to try to understand better how these work.

There is a little microswitch on the lock which there is a orange and a blue wire going to. There is clearly a signal wire.

Now this is strange, when the OSF door is locked with a key, there is approx. 1.6 volts to one of these wires and when the OSF door is unlocked, there is 12 volts to the wire.

The solenoid clearly actuates with 1.6 volts but perhaps not hard enough to physically pull the door button down.

Any ideas anyone?

citronut · Post by **citronut** » 11 Apr 2012, 08:21

firstly i think the micro switch is just to tell the system the door is open or shut,

secondly if the OSR door mechanism is attempting to lock i would think it just needs lubricating but not with that W stuff,

i find this is because the servo is not strong enough to pull a dried out mechanism down,

regards malcolm

Post by **Rhothgar** » 11 Apr 2012, 08:28

Morning Malcolm.

If not WD, then what is a suitable lubricant?

Also, it could do with all the rods and plastic moving parts lubricating too.

Do you know what the recommended lubricant is for plastic to plastic and metal to plastic?

Is it a PTFE based lube?

citronut · Post by **citronut** » 11 Apr 2012, 13:28

i use duck oil for lubing moving parts and i would think a silicon spray should be ok for plastic to plastic parts,

regards malcolm

Post by **Rhothgar** » 11 Apr 2012, 18:02

I have wasted the best part of 5 hours today looking at this damned problem. It's getting really frustrating now.

Facts:-

1) All the door buttons have been removed to ease load.
2) If I manually lift all buttons when I am inside the car, get out of the car and then lock with key, all locks go all the way down with the exception of the OSR door.
3) If I then unlock with key, nothing at all happens other than the driver's door unlocks. The solenoid does not activate.
4) The central locking control module clearly receives a signal as the relays inside is can be felt clicking.

Someone must have a clue what could be wrong here? Please help before I slit my wrists AND throat!

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