Recently I noticed that the headlights on my C5 were lit all the time. We have cleaned the sensor area on the windscreen but that hasn't cleared the fault. We have now had to disable the automatic light sensors and are using the manual switch. Don't know if it is connected to this problem but a few times when using the automatic key to unlock the car, the drivers door has remained locked, even though the remaining doors have unlocked. Has anyone got any advice please az I'd really like to get the automatic lighting working again. Thanks Liz