Front Parking Sensors Stumped the Dealer...

[Matt Kulseth]

Hey all. I've been lurking here whenever a repair comes up on my 2010 Lincoln Navigator. It's been a great resource. I try to do my own work unless a lift is required.

I just dropped $1k on diagnostics at the local Lincoln dealer with absolutely nothing to show for it. Hoping you all have some wisdom.

This summer the front parking sensor went on the fritz. Threw a non OBD error on the display. Beeped liked crazy anytime the car was in drive at low speed. No big deal right? Probably just a bad sensor. So I go and fiddle around with the sensors, replacing each until I find the bad one. No luck. Ok must be the parking sensor module in the back driver wheel well. Replaced it. Issue persists. Next I start replacing the speakers for the parking sensors under the dash and in the rear wheel well. No dice. My next thought was bumper wiring harness but I never got around to checking it. I end up just unplugging the speakers and hitting the reset button on the dash every time I turn the car on.

At this point I decide to just live with it until I have a compelling reason to bring it to the dealer for service. Last time I had been there I was disappointed in their ability to diagnose a transmission issue ($400 job morphed into $2k). You'd think I would've learned my lesson. I end up bringing it in to the same shop for a different issue and ask them to look at the parking sensor fault. I do a writeup of all the things I've tried and bring the extra parts.

$1k later the tech calls me and says he can't figure it out and would I like to authorize another few hours of diagnostics. He's done everything I've tried in the writeup and test the harness and found nothing. HELL NO brother.

Any thoughts on what to look at next? I told my wife I'm buying a lift this summer. I coulda bought a decent one with all the money I've spent at the dealer lately. Thanks fellas!

-Matt in MN

 

[Trainmaster]

If the bumper or perhaps its cover is at all out of plumb, you'll have this problem. It could have been dented, its supports bent, or anything else that would affect its geometry. Even worn shocks or a problem with the air suspension could do this.

The shop manuals will used to have all the measurement mounting angles called out. Don't know if they still do.

You have to look up the error code too.

Just a guess. Good luck and hope you get that lift one day!

I'd write to Ford Corporate and try to get my $1000 back. You paid good money and received nothing. Nobody should do business that way. Maybe they'll send you a toaster or a car wash coupon or something.

 

[99WhiteC5Coupe]

Hey all. I've been lurking here whenever a repair comes up on my 2010 Lincoln Navigator. It's been a great resource. I try to do my own work unless a lift is required.

I just dropped $1k on diagnostics at the local Lincoln dealer with absolutely nothing to show for it. Hoping you all have some wisdom.

This summer the front parking sensor went on the fritz. Threw a non OBD error on the display. Beeped liked crazy anytime the car was in drive at low speed. No big deal right? Probably just a bad sensor. So I go and fiddle around with the sensors, replacing each until I find the bad one. No luck. Ok must be the parking sensor module in the back driver wheel well. Replaced it. Issue persists. Next I start replacing the speakers for the parking sensors under the dash and in the rear wheel well. No dice. My next thought was bumper wiring harness but I never got around to checking it. I end up just unplugging the speakers and hitting the reset button on the dash every time I turn the car on.

At this point I decide to just live with it until I have a compelling reason to bring it to the dealer for service. Last time I had been there I was disappointed in their ability to diagnose a transmission issue ($400 job morphed into $2k). You'd think I would've learned my lesson. I end up bringing it in to the same shop for a different issue and ask them to look at the parking sensor fault. I do a writeup of all the things I've tried and bring the extra parts.

$1k later the tech calls me and says he can't figure it out and would I like to authorize another few hours of diagnostics. He's done everything I've tried in the writeup and test the harness and found nothing. HELL NO brother.

Any thoughts on what to look at next? I told my wife I'm buying a lift this summer. I coulda bought a decent one with all the money I've spent at the dealer lately. Thanks fellas!

-Matt in MN

Did you authorize the $1,000.00 charge prior to the work commencing? Interesting that the final charge was exactly 1,000.00.

 

[07navi]

Court is looking better by the minute here.

 

[tommyddsr]

You definitely need a new mechanic/dealership. Two strikes is more than generous from you. Just curious, do you have rear sensors also and are they working?

 

[Matt Kulseth]

Yeah the rear sensors work just fine. Such a weird deal. Thanks guys for the suggestions. I've had to bring the truck back since I got it back from the dealership. First time they incorrectly re-installed transmission module. I didn't make it far...

With this cold weather in MN lately it's been spitting power steering hoses everyday. The "oem" clamps they installed to "fix" my hose clamps aren't worth a damn. Honestly the experience at the dealer has been a nightmare. For what these guys charge you'd think they were brain surgeons. Only reason I went there in the first place was because I don't have the high end scanner to really dig in on the diagnostics. Lesson learned. If you can turn a wrench better to do it yourself.

 

[tommyddsr]

If the rear sensors are working I doubt it is the actual parking sensor module. I would start disconnecting one front sensor at a time and working back until the issue went away. Sorry I can't be more help but electronics are a bear to troubleshoot without being there. One other thing you can try is split the system in half first to troubleshoot. Figure out where the rear and front sensors all meet (module) and disconnect the front sensors. If this isolates it then troubleshoot the front sensors as noted above.

 

[99WhiteC5Coupe]

Yeah the rear sensors work just fine. Such a weird deal. Thanks guys for the suggestions. I've had to bring the truck back since I got it back from the dealership. First time they incorrectly re-installed transmission module. I didn't make it far...

With this cold weather in MN lately it's been spitting power steering hoses everyday. The "oem" clamps they installed to "fix" my hose clamps aren't worth a damn. Honestly the experience at the dealer has been a nightmare. For what these guys charge you'd think they were brain surgeons. Only reason I went there in the first place was because I don't have the high end scanner to really dig in on the diagnostics. Lesson learned. If you can turn a wrench better to do it yourself.

Did you approve in advance the $1,000.00 charge to diagnose the front sensors? What was the estimate to include?

 

[vincentrose]

With the engine OFF, turn key to ON, and put the transmission in drive. Then get out and go over to the front bumper, and put your ear right next to one of the sensors. You should hear a pulsating sound coming from the sensor. If you hear it, the move on to the next sensor, until you DONT hear anything. Once you found the sensor that is quiet, you've most likely found your culprit. I think a new sensor is around $50 or $60