75ZT Community

Some time ago the drivers door would not unlock using the key fob. Press the button and it makes a sound but does not unlock (although very occassionally it will).

I have obtained a new lock and at some point in the future I will replace it.

Yesterday, the NS rear one decided it would do the same.

Has anyone looked at a lock when this occurs and found out what makes them fail? And is there a repair

I had my OSR fail.

In fact it would fail to unlock first time after the car was locked for a while, but then start to work OK.

I stripped the assembly and it looked like the problem was too much grease around the motor causing brush contact problems. Unfortunatley this is a destructive process as the units are riveted.

So I think I know what breaks them, but it's not fixable by cleaning. Only option might be to operate the motors back and forth a lot to try to remove the grease by friction heat and gravity.

I may end up trying this as my replacement OSR has started doing the same. Don't think it's a connection problem as it was alright for 12-18 months after replacement.

All four door locks on my Tourer have been replaced at some stage - everytime the problem was the same - the nylon toothed gear within the locking unit had snapped. The tailgate lock has also failed but I was able to repair this by replacing the broken nylon part with a piece I made out of alloy plate.

Tourerfogey wrote:All four door locks on my Tourer have been replaced at some stage - everytime the problem was the same - the nylon toothed gear within the locking unit had snapped. The tailgate lock has also failed but I was able to repair this by replacing the broken nylon part with a piece I made out of alloy plate.

Ah - now if the gear can be sourced it will make for cheaper repairs instead of replacing the whole unit.

PaulT wrote:

Tourerfogey wrote:All four door locks on my Tourer have been replaced at some stage - everytime the problem was the same - the nylon toothed gear within the locking unit had snapped. The tailgate lock has also failed but I was able to repair this by replacing the broken nylon part with a piece I made out of alloy plate.

Ah - now if the gear can be sourced it will make for cheaper repairs instead of replacing the whole unit.

Not sure it can. I couldn't find any way to open the unit up that was non destructive. Maybe TF spotted something I didn't?

But it does seem there are two failure modes: no sign of broken gears in the one I took apart.

Any hints on dissasembly in a less brutal manner, Basil? I will have another to do when I change it again.

My door locks keep failing and then start working again a few weeks later! I've already bought both driver side units as I assumed they were stuffed. Passenger side ones have been fine so far.

And not always the same way either; the driver's door stopped locking off the remote but OK on the key, started working again and the rear door decides it will only open using the interior handle. Thank god I haven't put the child locks on!