After weeks of having pull a fuse out and replace to get the central locking, windows, interior light etc. to work. I have discovered if I unplug a rear door at the pillar the system seems to work. Before it would totally die after about 5 minutes. Anyone any idea whats wrong. I have checked the wires at the plug end only for now until I get time to remove door card. This suspect door seems to work Ok for a while (when plugged in). I am intending for this not to defeat me, as I do like the car.

bump

It's not unusual for the door controllers (an integral part of the window motor) to fail or to have corrosion at the connector. You haven't specified a year or trim level, so I'm assuming you have 4 power windows and convenience central locking.

ITs a Mk1 GXL 1.6 1999  Estate. I have changed the CCU

Edited 19 September, 201411 yr by fmcmoct

ITs a Mk1 GXL 1.6 1999 Estate. I have changed the CCU

The CCU under the dash uses CAN-bus to talk to the module in each door. When a module fails it can interfere with communications on the bus and this prevents the central locking from working. If it works when you unplug the rear door, I'm guessing that door has a faulty module.

I took the door card off this weekend. No corrosion to any terminals. Sprayed WD40 over all connections then Plugged everything back in and seemed to be working ok for the whole day. Then re-assembled door fully. It worked  all weekend but then packed up again Monday afternoon, back to normal. Is the door lock controller inside the window motor or the door lock? Not sure what best next step is.

Edited 23 September, 201411 yr by fmcmoct

Its controlled via the box on the window motor. Assume you sprayed wd40 on that? Take it off again and theres clips holding it to the window motor pull it off and check inside

Can the window motor unit be checked without removing from door, do I need to replace complete if unit has failed? Thanks for replying.