Just wanted to thank all of the forum members for previous posts, some of them many years ago, detailing their issues with their rear parking sensors.
I wasn’t getting any sound at all from the speaker and only one of the four sensors was clicking. I wired in a computer speaker and got the initial startup beep so I knew I had to replace at least the speaker. I then took each sensor and plugged them in the good harness and luckily they all clicked once plugged in. So I spent most of my Saturday finding and fixing broken wiring mostly near the sensors but two of the five breaks were in the protective looms further up in the bumper cover.
Anyway, persistence paid off, I now have fully functional parking assist. Although I never really park where I need it and I will probably install a rear view camera when I upgrade the stereo (gotta have Bluetooth).

 

I'm facing a similar issue- though the sensors seem to be live, it seems like neither the speaker nor the passenger side reverse light are.

​​​​​Do you have any tips on getting into the wiring? Is it mostly the sensor wires that are under the bumper, or did that include more of the general wiring for the rear?

 

novium, if your left side back up lights are working, but the right and parking sensors are not, then I would be looking at the wiring near the left tail light. Your problem is going to be right in that area. This is where having a wire tracer (device that puts a tone on a wire and you use a want to follow the tone, where the wire is broken, the tone cannot go any further and you are down to a few inches of wire to deal with) will make things very easy to fix. They are like $20 on ebay. This will save a lot of tearing apart of a wiring harness as the wand just needs to be within an inch or so of the wire to receive the tone.

 

I love doing things the easy way! Thanks for the suggestion, I wish I'd know about that when I was trying to get the wiring in the old sailboat working!