[subbus]

Hi, I have posted this question in the Tribaca forum but so far it has not been helpful.

I have OEM parking sensors on my Tribeca.

The backup sensors beeps even when there is no obstacle behind. It is not a continuos noise, it seems like the sensors do detect something.

I have tested the sensors while walking around with 2'x'2 board and they worked fine.

But in real world situation it beeps even when there is no obstacle making it completely useless.

Any ida what can be wrong?

Thank you.

 

[Saint J VT]

I believe ours beeps slowly in reverse as well. The closer you back to the object, the faster the beeps go.

The initial beeps are to alert you that you are in fact in reverse!

Here is the web site for the system we have:
http://drive2.subaru.com/Winter08_whatmakes.htm

 

[subbus]

Ours always beep like there is some obstacle. The frequency of beeps changes as the car moves but there is nothing around, flat surface. On top of it the sensors beeps when there is an obstacle. So I never know if it is a false alarm or real obstacle.

 

[Saint J VT]

Are your sensors facing downward, toward the road? That would do it.
Ours has sensors that are aimed pretty much straight back.

 

[subbus]

The sensors are facing slightly upward. They are installed in factory housings and mounted as high on the bumper as possible. Right above them is the bumper I-beam so they can't be mounted any higher for facing more upward. In other words the install seems OK.

 

[subbus]

It is installed as these (these pics are from a different car I found on web):

 

[Saint J VT]

With my owner's manual, I recall also receiving a card on how this system works.
I am almost positive, that, when I put it in reverse, the beeping starts, ever so slowly, to remind me I am in reverse.

I just checked with my wife, who mainly drives the OB.
She said she is not aware of it beeping when she puts it in reverse.

I do know that, even with the garage doors open, if the car is in the garage, it will beep when I put it in reverse. Whether it would out in the open or not, now I am not sure!

If you remove the back floor panels, then the left side panels (a screw may be needed to be removed where foldaway hooks are located), when that left side is off, the unit's "brain" box and extra wiring is all located in the bottom of the left fender, behind the left-rear wheel.

 

[subbus]

Based on the Subaru instructions when the reverse is engaged the system is suppose to beep once (if no obstacles around).

They also describe a test where the car is not started and while in reverse a person walks towards each individual sensors and the sensor suppose to beep continuously when the person is very close.

All this works. But in real world with no cars around on the parking lot it beeps with different frequency of beeps. When the car is out of the garage and stationary, there are no false beeps.

I sprayed back of the sensors with a soapy solution and let it dry. I will do more testing.

If that does not help I will locate the brain box, remove the wire connectors and clean them up.

 

[Saint J VT]

I wonder, if you are in a metropolis, could the system be picking up some kind of stray signals from something like radar, door openers, etc.:17:

I now think I recall that the single beep does indicate going into reverse. I thought there was something about putting it into gear. I have pajamas on and the car is out in the cold garage and it's snowing at the moment.

Perhaps the connection to the reverse light wire inside the back door is loose, thinking you are putting it in reverse more than once!

 

[subbus]

Thank you for all your ideas. Yes, it is possible that there is some bad contact somewhere. I think I will wait for warmer spring and take it all apart.

 

[subbus]

I sprayed Simple Green on the back side of the sensors where the wires are and let it dripped. That seems to help quite a bit. The sensors are very sensitive and beep when on snow or gravel but that is expected according to the manual.