Rear parking sensors beeping like mad!!!

[Dino D]

The rear parking sensors on my e46 have been driving me nuts.

The work fine sometimes and then for no apparent reason they go bonkers. Even though nothing is behind me the sensor emits a high pitched continous beep 1sec after I engage reverse. The beep is continous and does not interrupt even when there actually is something behind me.

I know that it will pick up a wall parallel to me when reverse parking but it does this even when there is no wall.

I thought the sensors may have been dirty so wiped them off with a tissue but no change.

Any ideas? I bought the car from an independant dealer who have looked it over but found no fault, especially since it worked fine the day I took it back!!

The owners manual tells me that the continous beep indicates the system is malfunctioning and that I should go to a main stealer....

I must add that I had a car wash and the guys could have sprayed the sensors with the jet wash. It has been worse since the car wash BUT it was doing this a fair bit before then...

[Robertb]

Defo a sensor has gone- exactly what happened to mine, and my father's 5 series. It should be replaced under warranty.

[Dino D]

Robertb said:

Defo a sensor has gone- exactly what happened to mine, and my father's 5 series. It should be replaced under warranty.

I'll check it out with the dealer. The sensor has started working fine now so its a real pain with these intermittentent problems as whenever I'm there it works fine...