My 1 series has developed a peculiar fault. Whilst driving, the headlamps suddenly illuminate, reverse lamp comes on intermittently and at the same time the headlamp switch freezes. The headlamps illuminate regardless of which position the switch is in, and when you turn the switch to dipped beam, the reverse lamp illuminates. Also, the indicators stop working, although the Hazard Warning switch works properly throughout. When this fault ocurs, the electric front window switches fail too, and when you try to lock the car after having exited, the front and rear sidelamps stay on. Last night I had to abandon the car in a locked garage because I couldn't shut the windows, and when I returned to it today the battery had discharged. Any ideas ???