PDC Sensor

[Ryansbmw1]

About 8 months ago, one of my PDC sensors started intermittently failing and eventually completely failed, shutting down the entire PDC sensor. Did the finger test to figure out which sensor it was and I also used Protool to double check- front center left sensor. Buy a new sensor, take it to the shop today to have it installed.

After installation, the PDC system is still not working. The shop said all the wiring looked fine but they didn’t have time to dive deeper into the issue today. Checked the fault on Protool and it still points to the same sensor. Tried clearing the fault multiple times but keeps coming back.

Any ideas what else it could be? I guess it’s possible the new sensor is faulty. Only way to tell would be to swap it with the center right one and see what happens

[ard]

Did the shop button the whole thing back up even though it wasnt working right?!?

[Ryansbmw1]

They squeezed me today because I was supplying the sensor. We all thought it would be a simple swap. Im not sure if they tested it before or not. They just got me in the waiting room saying it was done but the new sensor wasn’t working either. I’ve got an appointment to go back but I’m trying to see if I can diagnose it on my own. I can’t find a single post anywhere with an issue like this.

The one thing I did notice is that the little rubber coupler that goes around the edge of the sensor is missing, but that should effect it, at least not in sunny, dry weather. In rain, that could def be a problem.

[ard]

try bimmerfest, e70 forum. I recall quite a few threads on PDC issues.

[smassey321]

I had one of my sensors stop working when I switched to a LCI PDC. It did not throw an error on the screen until I disconnected it. I replaced it with a used sensor from ebay and all was fine.

Your issue may be wiring as you are getting an error. The wiring runs across the bumper to a connector under the passenger side headlight. https://www.newtis.info/tisv2/a/en/e...i-sav/GIglPkMh It then goes back and into the vehicle to the junction box module under the glove box. https://www.newtis.info/tisv2/a/en/e...5i-sav/S7y8Wyc

You can see the module end of the wiring by removing the kick pannel under the glove box. Look up for a silver screw and remove it. The junction box will tilt down and you can see the top side connectors. The PDC wiring is the smallest connector.

In the front bumper, pin 1 and 3 share the same wiring between all front sensors. Pin 2 for left front center (green/yellow wire) goes to pin 4 of the junction box PDC connector.

Click the below link for the wiring diagram. Then click on highlighted connectors to show their location in the car.

https://www.newtis.info/tisv2/a/en/e...ntrol/B4To5TUg

[Ryansbmw1]

Originally Posted by smassey321

I had one of my sensors stop working when I switched to a LCI PDC. It did not throw an error on the screen until I disconnected it. I replaced it with a used sensor from ebay and all was fine.

Your issue may be wiring as you are getting an error. The wiring runs across the bumper to a connector under the passenger side headlight. https://www.newtis.info/tisv2/a/en/e...i-sav/GIglPkMh It then goes back and into the vehicle to the junction box module under the glove box. https://www.newtis.info/tisv2/a/en/e...5i-sav/S7y8Wyc

You can see the module end of the wiring by removing the kick pannel under the glove box. Look up for a silver screw and remove it. The junction box will tilt down and you can see the top side connectors. The PDC wiring is the smallest connector.

In the front bumper, pin 1 and 3 share the same wiring between all front sensors. Pin 2 for left front center (green/yellow wire) goes to pin 4 of the junction box PDC connector.

Click the below link for the wiring diagram. Then click on highlighted connectors to show their location in the car.

https://www.newtis.info/tisv2/a/en/e...ntrol/B4To5TUg

Awesome. Thanks for the info. If it’s a wiring issue, looks like the green/yelllow wire will be the culprit or the pin it connects to junction box in the glove box. If it were a power or ground, since all the front sensors are tied together, it would have knocked them all out, correct?

[smassey321]

Originally Posted by Ryansbmw1

Awesome. Thanks for the info. If it’s a wiring issue, looks like the green/yelllow wire will be the culprit or the pin it connects to junction box in the glove box. If it were a power or ground, since all the front sensors are tied together, it would have knocked them all out, correct?

Sensor pin 1 and 3 is not shared until it all connects together under the headlight. There are 12 wires behind the front bumper and then 6 running to the junction box. But it is easy to check 1 and 3 by checking for continuity between a good 1 or 3 and the bad sensor 1 or 3.

Swap sensors first, then check for continuity between pin 1 and another pin 1 and then pin 3 and another pin 3 and finally check pin 2 green/yellow between the sensor connector to the junction box.