Rear reversing sensors

[Gary Waugh]

ladies & gentlemen, I have a 2008 EL and love it, the reversing camera still works perfectly but the sensors that detect when you are close to an object appear to not be working on the rear right hand side. I have never tried to get access to these, so i thought I would start by asking here. Do you have to remove the rear bumper to access them? or can they be accessed with the bumper in place? Is there any test procedure I can run to diagnose if a sensor unit is defective (no warning lights come on!) but I can touch an object on the rear right hand side of the car and it doesn't beep (the left hand side does). I believe there are 4 sensors in the rear, clearly my rear right corner sensor is not working, I want to see if it's as simple as the wire becoming unplugged or damaged with corrosion, but wondering if any of the other sensors are also not working? hence my request if a self test can be run, or if there is a simple test procedure to check each sensor.

Thanks Gary

 

[coolzzy]

If they are like the F150 units, you can access them from under the rear of the truck. If you have access to an inductive toner (used for many wiring diagnostics, especially telephone work), you will hear them click with the inductive wand. They get crud in the connections and might just need to be unplugged, cleaned, add some dialectic grease and plug back in. If there were a problem with the wire harness that runs them all you would get an error in the dash. On the pickups the wire harness plugs in above the spare tire, probably the same for the expedition, but if that were loose or damaged there would be an error. Ebay sells the replacement sensors on the cheap....

 

[Gary Waugh]

Thanks, will take a look this weekend.

Gary

 

[Flexpedition]

2008 uses one large sonar unit that is behind the bumper cover and above the frame mounted hitch. Its rectangular, maybe 2 inches tall, 5-6 inches wide, maybe an inch thick. On the silver backside you will see a single wiring connection near the middle, and there is a white sticker with barcode part number nearby.

I'm perplexed how it can work on one side but not the other. Might try unplugging it and see if that solves anything, though I am skeptical.

 

[Flexpedition]

Link to Rockauto showing the sensor that I tried to describe.
https://www.rockauto.com/de/moreinfo.php?pk=2064928&cc=1433530

Based on price, hope yours is still good.

 

[Gary Waugh]

Link to Rockauto showing the sensor that I tried to describe.
https://www.rockauto.com/de/moreinfo.php?pk=2064928&cc=1433530

Based on price, hope yours is still good.

Ouch!! Just saw the price!! I think if it has failed, I will be leaving it defective!! Cant justify $750 for a new box!! maybe try a breaker or scrapyard..

Gary