A customer in Shepperton got in touch about a composite front door that would no longer open properly from the handle. They were having to use the key to open it and could only lock it reliably from the outside because the inside handle would not throw the locking points.
From that description, a failed gearbox was already the most likely cause. It was unlikely to be a simple spindle issue or an adjustment problem, so I quoted on the basis of a gearbox replacement and the customer decided to go ahead.
Once on site, I removed the handles and confirmed the diagnosis: the gearbox had indeed gone rogue.
I had the correct replacement in stock, fitted the new gearbox and tested the complete multipoint system. The door itself was already sitting correctly and did not need hinge or keep adjustment. With the new centre case fitted, both the inside and outside operation were restored and the composite door was locking normally again.
