Park-Aid (Ultrasonic Rear Parking Assist) Help

[bpopilek]

OK, so I am trying to finish up a few last minute things to my '03 silhouette van before the weather gets too cold here in the mid-west!

Ever since I bought this van, the rear Park-Aid has not worked properly (IMHO). It will only flash a single red light as I back up normally. From all of the reading that I have done, the single flashing red LED indicates there is a problem with this system. And I also know that this system is separate from the rest of my ECM, therefore I cannot pull any codes on it.

From what I have found at this site (http://myweb.accessus.net/~090/cadidiag.html#urpa), I learned that I needed to ground the diagnostic connector to get my code readout via the LEDs, and then I could proceed with fixing the problem.

When I grounded the wire, only the outside 2 LEDs would flash over and over. I assume this to mean that there really isn't any error codes to read. So then I disconnected my ground wire and started playing with the system.

I noticed that if I backed up very very slowly towards a trash can (about 1mph tops), the lights would increase to indicate a object in the way. However, if I back up at a normal speed (3-4mph tops), only the outside red LED would flash. Does this indicate a problem, or does it mean that this system is only designed to be used at VERY slow speeds (1mph)?

This is the first vehicle I have ever had with this system, so I'm not sure if there is an actual problem or if I am just using it incorrectly. Any guidance is greatly appreciated! Thanks!

[dewaynep]

It's designed to be used at low speed.

[bpopilek]

Originally Posted by dewaynep

It's designed to be used at low speed.

But how slow of a speed exactly. If I just put it into reverse and coast backwards without any pressing on the gas pedal, it still errors out. I have to ride the brake the entire time at a snail's pace to keep it from just flashing a single red light at me. Is that behavior normal?

[lesterl]

What does the users manual say about the system? If you dont have a UM, download one from www.gm.com for free.

[bpopilek]

The user manual says 1-3mph for backup sensors to work. However, I have to ride the brake at a snails pace in order to stop the single flashing red light from coming on. And even then it doesn't seem to sense items behind me.

The only success I have had was my 1st test with a trash can. Now it seems to not sense anything, yet I still cannot pull any codes from it. Could the sensors be bad, but not bad enough that the system detects a fault?

[dewaynep]

That's too slow. You should be able to reverse at a "normal" speed. Perhaps it is an issue with the speed sensor connection to the vans speed sensor. You'd have to look at a wiring diagram to see where the 2 connect. I don't think you have a sensor problem, otherwise you would have gotten the code when you shorted the diagnostic connector.

[bpopilek]

Originally Posted by dewaynep

That's too slow. You should be able to reverse at a "normal" speed. Perhaps it is an issue with the speed sensor connection to the vans speed sensor. You'd have to look at a wiring diagram to see where the 2 connect. I don't think you have a sensor problem, otherwise you would have gotten the code when you shorted the diagnostic connector.

That's what I was thinking. Where can I find a diagram that shows the wiring? Should I just go ahead and pick up a Haynes manual?

[lesterl]

Probably wont be in the haynes manual....... www.autozone.com look up a 2001 Venture Rear Park Assist in wiring diagrams in the repair guide:

http://www.autozone.com/autozone/rep...96b43f8037148d

BTW I posted a 2001 because the 2002+ links to the pix are bad.....