Hi,
We have just fitted aftermarket reverse sensors to our Caddy Life. They are rear sensors only and do not connect to anything else, just the normal type that beep when getting close to something.

The sensors worked perfectly when testing before installing. They also work perfectly with just the ignition on, and this is where it gets interesting. When the car is actually turned on they beep on and off like there is something behind the car but there isn't it. Have checked the direction of the sensors etc etc...alll good. Turn the car off and just turn the ignition onto "on" and they are perfect. Turn the car fully on and bingo...beeping again.

It is a Caddy Life 2011. One install place that I called for advice told me I needed a reverse sensor interface at a cost of $200??? This doesn't see right?

What am I missing here? Any help would be most appreciated.