Car won’t lock or unlock from the remote

[Any1else]

Looking for a little pointer on an issue with the central locking on my Z4. The car will no longer lock and unlock from the key but it works from the lock. When I unlock the drivers door the passenger one doesn’t unlock and I need to unlock it separately. The fuel filler cap will unlock. I was researching a bit and the GM5 module may be the culprit but I wanted to check the collective thoughts on it before I send it away for repair.

1. Car won’t lock/unlock from the remote (doors or boot).
2. Doors unlock using the key but the central locking doesn’t work although the fuel cap locks/unlocks from the drivers door.
3. Boot release button works within the car
4. Interior lights work
5. Windscreen washers and wipers work

If it’s the GM5 I don’t have an issue getting it repaired but I would like to pinpoint the likely cause before committing to a repair. Issue is the same with both keys so I don’t think the issue is with the key.

Anyone else have this issue and managed to resolve it?

[tonyz4c]

It might also be the key battery.

I know a place where i have a problem to lock my car with my original key (almost 20 years old)
This week end i tried with another one which is 4 years old and no concern.

I can't remember when i changed the key if i was not able to start the engine
Or if i had only a Lock/unlock problem.
I will have to check as i still have this 3rd key

[Any1else]

Thanks tonyz4c - but because neither of the keys worked I figured it wasnt the batteries. I will change them and see if is resolves it.

[Any1else]

Changed the key batteries and sent the GM5 module away for repair but the problem is still there. Anyone know where else to look for the central locking not working?

[enuff_zed]

Changed the key batteries and sent the GM5 module away for repair but the problem is still there. Anyone know where else to look for the central locking not working?

A random suggestion, but have you had a new windscreen? Wondering if the plug hasn't been put back on the rear view mirror?

[Any1else]

A random suggestion, but have you had a new windscreen? Wondering if the plug hasn't been put back on the rear view mirror?

Thanks enuff_zed but no, windscreen hasn’t been replaced.

[Any1else]

Checked a few posts on here and one mentioned checking fuse 30 but it was intact. Another suggested disconnecting the battery for a while so did that but it didn’t help. Programming the key doesn’t work either. Could it be the receiver? If I understand correctly it’s in the rear view mirror.

[enuff_zed]

Checked a few posts on here and one mentioned checking fuse 30 but it was intact. Another suggested disconnecting the battery for a while so did that but it didn’t help. Programming the key doesn’t work either. Could it be the receiver? If I understand correctly it’s in the rear view mirror.

Which leads back to my question about the windscreen

[Any1else]

Cheers enuff_zed but the windscreen hasn’t been replaced. Definitely.

[Any1else]

Took the rear view mirror off and cleaned up the connections and made sure that both cables were connected properly. Everything tidy and secure but the key still doesn’t do anything off the remote. Doesn’t even activate the gap tech for the roof. Anyone got any ideas what it might be?

[Any1else]

Should just have waited for the GM5 module to be repaired and held off on the key battery (that seemed an easy fix) but instead I did both at the same time. When resoldering the battery the heat can affect other components on the circuit board and thats what I did. After much investigation work in the car and contacting about half a dozen key guys that couldn't help, found a guy on ebay that fixed the key for me. Really pleased to have it sorted and the remote working again. Take-away from all this - don't DIY resolder the key batteries.