I have recently purchased a 1993 E36 325i coupe. I was suprised to find it fitted whith what I assume is a factory fitted set of rear parking sensors (perhaps somebody can confirm factory fitted)
Basically they dont work. I have an Auto box and frequently when I shift to reverse after having been driving, they beep constantly for around 4 seconds then stop. other times when I shift to reverse they dont make a sound. In either case when I approach a wall, they never make a sound regardless of how close I get.
I have had the car 2 weeks, and on ONE occasion they worked PERFECTLY. I moved away from the wall and back again a dozen times to test and it was sweet! - but only this once.
This suggests to me the curcuit has power so it cant be fatal? - Also the fact that there is frequently a tone when I shift to reverse gear must be a good sign?
Is there a control unit for this system hidden away somewhere? - Is there anything obvious to check?
Any help would be very much appreciated.