Hi Folks

When I engage reverse, instead of the proximity beeps I normally hear, intermittently I'm getting a constant high-pitched sound and the sensors don't work.

If I then come out of reverse... and then engage reverse again, it's fine.

It's happening about 50% of the time I engage reverse.

Any ideas?

Cheers, Neil

 

If not a bad/dirty sensor, remove spare tyre and check all around for the slightest signs of damp or water.

 

Here in the extremely rainy Pacific Northwest (USA), my '05 STR has been struggling with our record-breaking rains this season. The park sensor module spent some time underwater in the trunk before I found the problem with the trunk seals. I have an electronics background, so I was able to remove the module, clean it and test everything. It was fine, so I reinstalled it. Now, if the sensors get too wet, I get the same symptoms as the OP.

No problems whatsoever with the front sensors, though, and they get BLASTED with road spray and gunk constanly for 6-7 months here...

Ken