A customer in Woking got in touch because the front-door locking mechanism had developed an intermittent fault.
When I arrived, the door happened to lock and unlock normally, but because the customer had experienced the problem repeatedly I removed the mechanism for a proper inspection.
I opened the gearbox and found a small spring and ball bearing out of position and interfering with the moving components inside.
They were not playing a vital role in the operation of the system, so I removed the loose pieces and rebuilt the gearbox.
The mechanism then worked much more smoothly.
I made it clear to the customer that this was a temporary repair rather than something I could warranty as a permanent solution.
The customer was happy to keep the original mechanism in service and get some more use from it before eventually replacing it when it failed completely.
