I'm surprised that someone would suggest that the sensor vibrates. As far as I know, they're just a small little chip with an infrared light to detect distance.

I would've suggested going to a junk yard to find a Escape or Mariner with the rear bumper still available, yanking the sensors and maybe testing them. Are they individually connected to a larger harness or are all four routed to the one connector?

If the former, then maybe you could just secure one sensor and remove/replace until you find a bad one?

 

I'm surprised that someone would suggest that the sensor vibrates. As far as I know, they're just a small little chip with an infrared light to detect distance.

I would've suggested going to a junk yard to find a Escape or Mariner with the rear bumper still available, yanking the sensors and maybe testing them. Are they individually connected to a larger harness or are all four routed to the one connector?

If the former, then maybe you could just secure one sensor and remove/replace until you find a bad one?

I'm pretty sure you can replace the sensors individually. Certainly they're sold individually.

Problem is, that I don't know that a sensor is the problem. So any effort replacing a sensor might be wasted if the problem is elsewhere.

Since the service manual says there are codes associated with each sensor and other parts of the system, I'm going to see about having a mechanic check for codes.

(Which raises a good question. Given the vast array of other computer/electronic features on these cars (and all the others), why don't the manufacturers just let you display the OBD codes on the dashboard? I know the answer: they want us to be dependent on them to fix their deficient products.)

 

FORScan will probably be able to pick this code up, but you may need to modify the hardware to read on medium speed CAN. See the first link in my signature.

 

My buddy's 02 jeep reads codes for him, flip to on three times and id displays on the dash.

but you are right and why would Ford pay to deliver a service a vast mwjority of people won't use and those that would probably have a better scanner

 

Sounds like one or more of your sensors is dead.

You'll be pleased to know there is an easy way to diagnose

Get someone to sit in the car and put it in reverse for you and keep the brake on!!! Put on the Emergency Brake for safety.

Tell the "driver" to put it in reverse when you have an ear directly over a sensor. You should hear a faint clicking sound. If you don't, the sensor is dead. Repeat this for all four sensors

Then, hit ebay where you'll find sensors sold individually or in packs of four for a very reasonable price. Pull out the dead sensor and look carefully on the outside and you'll see a part number. Simply replace the dead one(s).

I had to do this a couple of months back. I had only one sensor out but bought the pack of four anyway. Replacement takes two mins.

No need for fault codes etc etc

Stu

 

Emissions codes are required by law to be readable by standard obd II code readers. All other codes, not so much. Forscan is the way to go.

 

A mechanic from the garage I use came by with a fancy scanner, and said his scanner indicated the left corner sensor was bad. He also gave me the code C1707.

I took the sensor out of the bumper. There was a lot of grime caked on it, but it was completely clean inside the connector.

So there are 4 clips on a seam around the barrel of the sensor, and there are 4 holes closer to the outside end of it. The holes look like drainage holes. I thought I'd open the barrel and probably find dirt to clean out. The 4 little clips are difficult to open without breaking, and then I managed to get the parts separated. Well, it turns out separating these parts destroys the sensor. There's some sort of black goo inside with a couple of very thin wires. Separating the halves breaks the wires.

I went to the service manual, and it refers to cleaning the sensors with pressurized water. So maybe this means you can flush out the barrel of the sensor, and so perhaps resolve a failure.

But I also checked the codes, and C1707 is the middle left sensor, not the corner sensor. I probably wrecked a good sensor and have yet to take a look at the middle left one.

Anyway, I decide to patronize the local Ford dealer for new sensors. $210 each. Are they kidding? So I order two online for $15 each with free delivery in a few days.

 

The new sensors arrived, I installed them, and the reverse sensing system works fine now.

Interesting that the inner left sensor was clean, while the outer left one was very dirty. I'll keep the clean one for next time in case the diagnostics were mixed up and it's actually ok.