issues with park aid system on my '08 Sport Trac...

[sgoss66]

Hi all...

My "park aid" system stopped working. It was fine for the past few years, and then for about a week it would work intermittently (sometimes it would, other times, when placing in reverse, I'd get a "check park aid" message). Now, for the past couple of months, it won't work at all -- just the "check park aid" message any time I put it in reverse.

I figured that one of the four sensors went bad, so I bought one, and started to sequentially swap them out to see which one was bad; pulled the first one, and put in the new one, and then checked -- still got the "check park aid" message. So, I put the old one back in, and moved to the next one. In trying to remove the second one, I broke it -- SO, I installed the new one, and then just went ahead and bought two more new ones -- and replaced the last two sensors with new ones. Still however, I'm getting the "check park aid" message. I pulled all four (three new, one old), and re-installed, to be sure none were loose. Still not working. At this point, I don't know what to try next. Anyone have any suggestions? I also checked the wiring, and don't see any visible damage of any sort...

Steve

 

[sgoss66]

Does anyone have any ideas on this? I would like to avoid taking it in to the dealership for a diagnostic, if possible...

Steve

 

[Trac Marks]

I don't have this feature so have 0 knowledge, but it looks like somebody put together some good notes in this thread. Post #7 . The module on a ST obviously isn't in the hatch, rather I believe its under the drivers side of the dash, lower knee bolster, right above your right knee while driving. Maybe it just needs the old wiggle test?

http://www.explorerforum.com/forums//showthread.php?t=153264


I also recall reading another thread (here or another forum) that suggests when you replace a sensor (or 3 like you), you have to do some sort of Park Assist module reset..... something along the lines of turn key on, wait X number of seconds, turn lights on, key off... don't recall the sequence of events, but point is the module needs to reboot or whatever. Worth a search.

 

[sgoss66]

Trac Marks --

Thanks for the reply. I couldn't find anywhere, in an online search, where it outlines the procedures for a "reset" of the Park Assist Module, but on a separate note, my battery died last week, so I had to replace it. I would think that unhooking the old battery, and hooking up the new one, would have "reset" everything, but not sure.

BUT, I know know something I didn't, before, thanks to your post -- which is that I may have a bad Park Assist Module. I'll have a look to see what a new module would cost, and see if I can find where it is (i.e. if it is indeed under the dash/above the right knee).

Steve

 

[Trac Marks]

Appears I was mistaken that the module is in the dash - according to some online service manuals, its in the rear passenger corner - both SUV & ST Explorers.


SECTION 413-13: Parking Aid
2008 Explorer/Mountaineer/Explorer Sport Trac Workshop Manual

Explorer Sport Trac
The parking aid system utilizes ultrasonic technology only. The 4 parking aid ultrasonic sensors are located in the rear bumper cover.

The parking aid system consists of the:
* Parking aid sensors (located in the rear bumper cover)
* PAM and speaker assembly (located behind the passenger rear seat)
* Parking aid disable feature (integral to the instrument cluster [IC] message center)

One would think disconnecting the battery would (or should) reset all things electronic, but doesn't always.

Do you have access to a code reader?
U0159 - Network - Lost Communications with Park Assist Module

Fuse #18 / 10 amp (red) powers the module.

Here is a schematic:
http://arrc.ebscohost.com/searches?car_uuid=1441670&fa_uuid=uuid_p5_wiring_diagram_205034583115824497652789649725485046600&filters%5Bservice_information_type_path_facet%5D=root%2Fmrt%2Fsit%2Fp5_diagrams&keywords=parking

 

[sgoss66]

Trac Marks --

THANKS for the additional info.

I do not have access to a code reader, but I know of a local shop I have used in the past that will do a quick diagnostic with a hand-held code reader...I will stop and ask him to check for the U0159 code.

I wonder if, if it were a fuse issue, there would be other issues manifesting themselves, or is that fuse dedicated to the park assist system only?

The link for the schematic didn't work...

 

[sgoss66]

As an aside, it looks like THIS:

8A2T-15T850-AA

...may be the part number for the Park Assist (Driver Assist) module for an '08 Sport Trac? I haven't found one for sale online yet...

 

[Trac Marks]

Fuse 18 also supplies power to IVD switch?, IVD?, 4x4 module, 4x4 switch, Heated seat switches, Compass, Electrochromatic mirror, AUX climate control .... so it is likely a long shot, but worth looking at. I think the compass & mirror are standard on all ST's, so likely you'd notice them not working.

8A2T-15T850-AA -- can't comment if its correct or not, but would almost expect the module (behind passenger rear seat) to have this or another part number listed on it somewhere.


WELCOME - from a fellow OKIE up the turdpike here in Tulsa!

 

[sgoss66]

Greetings, fellow Okie!

Thanks for the wiring diagram.

Yes, my ST has the Electrochromatic mirror, the compass, heated seats, etc. I obviously might not notice if the 4x4 switch is working, or the heated seats (it being summer!), but I do know that the climate control is working, and I'll check on the compass but I'm 99% sure it's working as well. Assuming it's not a fuse, it HAS to be either sensors, or the module. I guess it is possible that one of the new sensors I ordered is bad, but that would be an unusual chain of events (I just happened to install the one bad "new" sensor into the spot where the bad "old" sensor was).

I'll have it checked for codes at the mechanic, and I'll see if I can find the module behind the rear seat...

THANKS for your help!

Steve

 

[sgoss66]

Hi, all. I'm resurrecting an old thread here, because I never did fix this problem, but I'd like to have it fixed.

My Park Aid system is not working, as was the case when I started this thread. I just purchased four new sensors and installed them. That did not fix the problem; the instrument panel still says "check park aid" when I shift into reverse.

I am pretty sure it is not the fuse, based on the information from user Trac Marks (as the fuse he specified, #18, controls other things that ARE working). So, it would seem to me that it must be the Park Assist Module (PAM), Ford item number 8A2T-15T850-AA.

However, I can't figure out where this module is. Trac Marks says it is behind the back seats, but all that I see back there that is "obvious" is a sub-woofer. I took off the plastic housing behind the seats, below the rear window, and looked behind the sheet of padding underneath the plastic housing, and again, nothing obvious. There is a metal "plate," behind that sheet of padding -- held in with several bolts; I did not remove this "plate" to see what is behind it, but I could remove the padding and then remove this metal plate, if that's where the PAM is located. But before I did all of that, I wanted to see if anyone knows if that's actually where the PAM is located.

If anyone has any other thoughts here, I'd appreciate it. I think with it not being the sensors (and, for what it's worth, NONE of them "click" when it's in reverse, as I understand that they should be, if they were working properly), and not the fuse, it almost HAS to be the PAM (unless the wiring going back to the sensors is somehow damaged, which I doubt).

Steve

 

[kenadams93]

Hi sgoss66, I know this is 5 years later but I just bought an 07 Sport Trac and has a Check Park Aid error, none of my sensors were good so i swapped them all out. The error is gone but the sensors don't beep with Park Aid ON and in reverse with an object close to the rear. Did you ever find the PAM? I'm going to go looking for mine to disconnect and reconnect to it trying to reset it. Thanks.