Car won’t unlock - help!

[Dr Mike Oxgreen]

I have a ‘99 450.

About an hour ago I locked it, and now it won’t unlock.

Pressing the fob button causes the hazards to flash once, but the doors don’t actually unlock. There is no sound at all. The buttons under the mirrors activate the solenoid, but the door(s) don’t open. Both doors behave the same way, so it’s not a failed solenoid.

Pressing the fob button again to “lock” it causes a slight sound, as if locking when it’s already locked, and the hazards flash twice.

I have two working fobs, and they both do exactly the same. So it’s not the fobs.

If I put the car into the “unlocked” state and then break in using the laughably simple technique, I can reach in and turn the golf ball to open the door. Then I can turn the ignition on, press the fob button, fuel pump primes, and I can start the engine. So the immobiliser isn’t completely dead, and the battery seems fine (I drove it quite a bit earlier).

Pressing the button on top of the golf ball has no effect - it makes a slight noise, but it doesn’t make the doors work properly.

So what has gone wrong?

[Dr Mike Oxgreen]

I don’t fking believe it!

I just went out to try another idea (I thought I’d put it on the Accumate for a while), but now the doors are unlocking perfectly!

So it looks like I have an intermittent problem with unlocking.

I’d still appreciate your thoughts!

[Dr Mike Oxgreen]

… and now it’s back to its faulty behaviour.

[Dr Mike Oxgreen]

Current “arguido” is the passenger side door switch, which did seem a bit inconsistent in its behaviour when prodded.

I’ve unscrewed it, sprayed it with half a can of contact cleaner, exercised it, and screwed it back in.

It does now seem somewhat more consistent, and the doors are locking and unlocking as they should.

Place your bets as to whether the problem is fixed…

[Belle427]

Those switches are the main culprit, it may be corrosion on the contact which is difficult to shift with contact cleaner.
If it continues to play up I’d remove them and clean more thoroughly, make sure the attached negative cable is good too.

[carl350i]

I had a similar issue with my griffith.

In the end, I removed the fuse for the alarm, it wasn’t blown, refitted it and it cured the problem. I was actually intending to pull the fuse for the central locking but pulled the wrong one…… It was next to it in my defence..

Dirty contacts at the fuses, may be worth checking.

[s p a c e m a n]

And I had a problem with the central locking relay under the dash. If I smacked the top of the passenger side dash it would work again, same symptoms as you. Managed to find a new one on eBay but it was something weird and specific made 30 years ago

[TR4man]

TVRs - don’t you just love them!

[Dr Mike Oxgreen]

Thanks for the pointers!

[Adrian@]

Go back to where the car was parked and look on the floor for the circle of rubber that was stuck to the door and sets the door switches limits (it is common for these to fall off over time). On later cars there is a plastic limit riveted in place. A@