interior lock button

This may be a common fault as it does it on both the coupes that I have but when I press the interior lock button on the dash it tries to lock the doors but then immediately unlocks them.

Anybody had this or know how to cure it?

Many Thanks

I take it your central locking works perfectly normally when outside the cars?

One of the doors, or less probably the alarm system, is holding the system unlocked. The most likely cause is the microswitches in one of the lock units - isolate the door by removing the door loom at the big white connector in the A-column - but another possibility is the light in the boot.

The switch that turns it on is on a tab of metal which gets bent so it never turns off, and that tells the alarm not to lock the doors.

Incidentally, it eats your battery quite quickly too, but you'd probably notice that.

Yes it does, it locks with the both doors with the key from the drivers door.

Thanks I'll give it a try and report back

Ah, that suggests that the fault may be the driver's door not actually locking when commanded by the electrics. The test would be to try locking the passenger door with the key.

I've just sorted this issue on my coupe, car would lock ok using driver door lock, but the locks would pop back open when locking using the passenger door or the dash button.
With mine, the drivers door lock mechanism had been over-greased and attracted dirt, the extra friction meant that the door motor didn't have the strength to operate the lock properly and popped back.
By removing , cleaning and lubricating it sparingly, it's now working as it should.
Hope this helps
Alex