Q I have a 2000 528i automatic. When I select reverse gear, I get a constant beep for 5-10 seconds. The light on the PDC button flashes also. What do you think is causing this?

Mark Rayner, email.

A It’s simply a faulty sensor. To find out which one, engage reverse with the ignition on but engine off, and listen to the sensors – you should hear a clicking sound and the one that is silent is faulty.