Vectra C 2.2 Elite Interior Courtesy Lights not working when doors open

[Dobs]

Hi All

I've got a 2004 (04) Vectra C 2.2 (Z22YH) Elite where the interior lights are not working when the doors are opened or the car is unlocked.

When the car is unlocked, the number plate lights, dashboard lights and infotainment screen all come on for about 10 seconds. Interior lights (Front and back) don't.

When one of the doors is opened, dashboard, infotainment display, climate control lights and the buttons on the light control unit in the roof/ map reading light buttons all light up but the interior lights do not.

All interior light bulbs are good and all work when manually turned on. Map lights work and all 4 (2 in the front 2 in the back) come on when the button in the roof is pressed.

I've checked all the door and boot sensors and they all work (show up on the red display on the dash when open)

On one occasion after manually turning the interior lights on and off, the lights then started to work. Off when all doors closed, when the door opened lights come on and after door is closed, lights stay on for about 20 seconds before dimming down to off. After locking and unlocking the car, the fault reappeared.

From reading, i learnt the interior lights are fed from the rear fuse box in the boot via a ribbon cable in the roof and the lights are controlled by the BCM.

I don't think a fuse is the problem as the lights work when manually operated, could the loom in the roof be at fault or could the BCM be corrupted and requires resetting by disconnecting the battery. Could the front interior light box in the roof where the switches are be at fault?

Wondering if anyone has come across a similar issue and is able to advise. Many thanks in advance.

[northpole]

it'll have logged a faultcode, so i suggest you get the car on a diagnostic scanner.