my wife owns a F plate nissan micra 1.2 gsx. she is owned it for 4 weeks everything is fine, however the previous owner told her that the reversing light do not work. we've had the car to our local garage to find out why. he told us that the sensor was not working. I've changed the sensor, from the wife is old F plate 1.2 micra. this has not worked. I've checked all fuses,earth leads,bulbs even the wiring from the engine to the fuse box then onto the rear lights, There is no crimping (crushing) anywhere on the wires. I am now stumped as to what has caused it to fail.
could it be becausethe previous owner put a new cd player/radio into the car?

please burn it