Z3 central locking not working. Any ideas?

[Tommy-boy]

I have just purchased a Z3, 1997 R reg, which I am thrilled with but the central locking doesn’t work! The key (battery-less) will open both doors and the boot manually but I can’t lock the car from just the driver‘s door ( or the passenger door or the boot for that matter.) I have looked in the owner‘s manual but couldn’t locate any useful information.
I would really appreciate any advice.

 

[jonco]

I have just purchased a Z3, 1997 R reg, which I am thrilled with but the central locking doesn’t work! The key (battery-less) will open both doors and the boot manually but I can’t lock the car from just the driver‘s door ( or the passenger door or the boot for that matter.) I have looked in the owner‘s manual but couldn’t locate any useful information.
I would really appreciate any advice.

Need some more info to assist. There are 2 separate methods of locking i.e remote lock with fob and central lock with key,
Please clarify what you mean by `battery-less' - do you have a remote locking fob? Looking at the year of manufacture suspect you should have what is commonly known as the half house-brick fob - see attached as example. https://zroadster.org/articles/3g-ews-remote-fob-programming.24/

The car should centrally lock using the key in any lock. The common problem , but not always the problem, is a broken wire(s} in the wiring loom which passes from body to boot lid often referred to as the `loom of doom'.

 

[Tommy-boy]

Much appreciate your detailed reply. The second method you mentioned ie trying to activate the central locking using the key is what I have tried but alas to no avail. I do have two remote locking fobs. However, they had no batteries in them so I’ve ordered two replacement batteries and am currently awaiting their delivery.

 

[jonco]

Much appreciate your detailed reply. The second method you mentioned ie trying to activate the central locking using the key is what I have tried but alas to no avail. I do have two remote locking fobs. However, they had no batteries in them so I’ve ordered two replacement batteries and am currently awaiting their delivery.

If the batteries have been out for a while you will need to reprogram fobs for them to work remotely.
However, the central locking aspect, using the key in lock, should still work irrespective. The usual suspect is broken wire(s) in the loom of doom but it could be a door lock actuator. There are a few different opinions as to how to check loom of doom. I would suggest you remove grommet where it enters boot lid and carefully cut inner sheath to expose cable. When you can see individual strands (7 of) hold cable at body end carefully pull one strand at a time at exposed lid end to check for breakage. Hope that makes sense.
Note - if the key will not work then the remote cannot.

 

[Dxbolton]

Let’s start at the easiest place.
Have you checked the fuses?
there are two from memory, both inside the same box inside the engine bay

 

[jonco]

Let’s start at the easiest place.
Have you checked the fuses?
there are two from memory, both inside the same box inside the engine bay

Fair comment

 

[Tommy-boy]

That’s where I’ll start. It makes sense. Need to check the manual as to which fuses I need to look for and their ampage value. Don’t like the sound of this ‘loom of doom’, sounds ominous!

 

[Dxbolton]

When you lift off the fuse box cover it has the locations and uses of each fuse written inside.
You can also buy a replacement loom section to splice into your loom to make the boot repair if required

 

[Dxbolton]

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[Fender2004]

If the batteries are not in the half brick remote, it could be just a case of programming them to the car, once new batteries are fitted, then they should work.
As Tommy-Boy has said the central locking works with the key, so this proves that the system works. The fob is just a different way of operating it.

 

[Rob76]

I had same bother someone replaced the rear view windscreen mirror with a non standard type which did not contain the RX for the remote locking!!!!!!!!!!!!!!!

 

[Tommy-boy]

What a great forum, so many people making sound suggestions. Batteries have now been fitted to both ‘bricks’. One has the red led on permanently and although I’ve checked for sticking keys it appears to be faulty. The second ‘brick’ after a stuttering start now appears to be working although the time lag reminds me of Corporal Jones in Dad‘s Army when on parade. But the great news is that following one suggestion I checked the fuses and found fuse 7, 5 amp, was blown. I have now replaced the fuse and am now able to lock and unlock both doors and the boot from the driver‘s door. Bring on the sunshine itching for an open top ride.

 

[jonco]

..............But the great news is that following one suggestion I checked the fuses and found fuse 7, 5 amp, was blown. I have now replaced the fuse and am now able to lock and unlock both doors and the boot from the driver‘s door. Bring on the sunshine itching for an open top ride.

Good progress. If you lock passenger door or boot with key - what happens? Presuming you have the half brick fob, I'll send you a copy of supplementary manual for remote if you haven't got one when I get a minute.

 

[Tommy-boy]

No I don’t have the supplementary manual and would very much appreciate a copy. I checked this morning and am glad to report that all locks activate the central locking.

 

[jonco]

No I don’t have the supplementary manual and would very much appreciate a copy. I checked this morning and am glad to report that all locks activate the central locking.

Good - have sent you a copy through conversations.

 

[t-tony]

Nice of you Colin.

Tony.

 

[Paulie]

Hi all,

I don’t mean to hijack the conversation but I have a similar issue but only the passenger side door. Sometimes it unlocks with the fob (aftermarket) but most times it doesn’t.
Any ideas on the probable cause?

Thanks

 

[t-tony]

When I had this on my Z3 it was the accuator solenoid in the N/S door which was faulty.

Tony.

 

[Paulie]

Thanks Tony. I’ll check that out

 

[Rob76]

I bought a second hand rear view mirror for my pre wide bodied Z3 1999. However not sure I got the right one I require the wireless version. Does anyone know the part number of this item which hopefully is the number stamped on the mirror I bought. Number shown on unit is I E1 010458
Thanks