SundanceUK

Fine work, Mike, posting these up gives us a good idea of whats inside, the switch bank looks quite robust and really, the lock motor should work forever and a day, its just the plastic gears and sliders, work of the devil!
I think I found in mine that the root cause of the issue was the worn plastic bush in the key barrel lever, stopping one of the rods to pull the switch properly, hence the machine gun rattle of the locking motor.
This may be a common problem and would be the first thing I will now check with a faulty locking unit.

Sundance