Parking Sensor Fault

Hello All,

Hope someone can help with this.

Finally got around to doing these.

After removing and cleaning up all of the sensors I went back to replacing them and only then realised the colours of the group of three wires going to each sensor are different!

I have found some diagrams online but nothing that has helped so far.

I have connected all of them where I thought the wires were before but apparently three are wrong! The first one (far right) has the correct wiring as I had a previous photo, the others I think are all wrong as if I put the van in revers all three act as if something is behind the van already.

Hopefully someone can say which order the wires should be in for the remaining three. Sorry for the blurry photos, the sun seemed to make them really hard to get clear.

Bear in mind mine is 2014/2015 T5.


Right (correct)
View attachment 65662


Second from right (probably wrong)
View attachment 65663

Second from left (probably wrong)
View attachment 65664

Left (probably wrong)
View attachment 65665

Sorry I should have added that I eventually found out how to remove the individual wires from the connectors ( see my post #11). To remove all three the purple clip must be completely removed then all three slide out, and as you see in the picture below there is a silicone seal around the wire that slides in the hole.

View attachment 65669
Perhaps this might help you.

Screenshot_20200410-234542_Drive.jpgScreenshot_20200410-234606_Drive.jpg
Screenshot_20200410-234619_Drive.jpg
 
  • Like
Reactions: mmi
Looking at that last pic - I would definitely replace those terminals if they are all as corroded as that one. You are only putting off failure again with poor contacting. Is there any clue as to the route of the water into the housing as the wire seal looks good and clean. New housing and terminals + making sure that all seals are present and the grease as backup.
 
Yep oldie but goodie ordered new ones but the chap can't send out until the current unpleasantness ends so only doing this to double check no other faults in the system and I've not much else to do currently.

Can't for the life of me work out how the wet got in, in fact they were more than wet looks almost muddy in there! No reason to think anyone had them apart and left them like it in the past but surely you would clean them before re-installing if that was the case?!
 
did you ever figure out the wiring? I'm in a similar boat, put a new connector on the driver /right side as it was corroded - 2015 T5 - I think because mud built up over the sensor keeping moisture in? anyway, on rewiring with a new connector and the individual parts on the cable I now get a red 'something in immediate vicinity' signal before it says optical system not operational. I wonder if I connected it wrong but the only one I rewired was the right/driver side one and it is I think the same as your picture (ill be taking it apart again when I get time so will double check!)
 
Just compare the wiring to the other plugs, all the connectors have a common +ve and common -ve then a return wire from each sensor
 
Just compare the wiring to the other plugs, all the connectors have a common +ve and common -ve then a return wire from each sensor
thanks - thats what I did - I was just curious as I got the same fault after rewiring as the OP so wondered if we had made a similar error. tbh I suspect I probably damaged the wires to the sensor - I didn't have a small enough crimping tool so put the individual connectors on with pliers and they ended up being a bit of a squeeze into the 3 holed receiver. will have another go and see if I can sort it - the dreadful loud beep freaks me out every time I go to reverse! :)~
 
I have this problem again but this time on my sisters van, a 2013 T5.1.

On my own van (earlier in this thread) I started by blowing out the connector previous mentioned behind the rear nearside quarter panel, which didn't work, and in the end I had to replace all of the connectors that plug into the actual sensors.

So of course on my sisters I started with the sensors. Well in this case they are fine, in fact I would imagine they have been replaced as there is no wet or mud in them like there were with mine.

I did do the basic first or removing them one at a time to clean and there is no sound coming from any of them.

From what I understand other possibilities are the module under the steering wheel and a connector under the passenger seat.
  • I can't acces the rear nearside quarter panel easily, it has been lined with carpet in one piece with no panels. I don't know if I can get access to the connector by taking off the bumper and pulling the cable gently towards me, as I can't remember from doing my own, and to look would mean removing my rear seat/bed to access the panel. Or anyone know another way of getting in there?
  • Does anyone know how to identify the connector under the passenger seat? To me it looks identical to own (picture of mine attached) and I can't recall anything that looked like it could be this when I did my electrics.
  • Has anyone ever had an issue with the module end? I have found plenty of people online saying how to check it and how hard it is to access but nobody who has had one fail yet!
  • Anything else I can try?
I do have VCDS, but currently don't have windows on my laptop. If I sort this out a) Will this necessarily help pinpoint the issue? b) How do I go about it? It's ages since I've used it!

Thanks in advance for any help.

NSR_Panel.jpeg

Under_Seat.JPG
 
I do have VCDS, but currently don't have windows on my laptop. If I sort this out a) Will this necessarily help pinpoint the issue? b) How do I go about it?
Certainly would help - just do an Auto-Scan - you can do a dry-run without actual VCDS here --> Ross-Tech: VCDS Tour

The Scan should report what's not working electrically - disconnects, failed sensors, etc. - under Address 10: Park/Steer Assist
A few fault codes here --> https://t6forum.com/threads/vcds-and-carista-fault-codes.14143/post-231838

The actual sensors can be interrogated using function "Advanced Measurement Values" (VCDS > Select Control Module > 10-Park/Steer Assist > Adv. Meas. Values

EDIT:
how to identify the connector under the passenger seat?
T5.1: black 10-pin connector under left seat - actually the same in T6.
 
Certainly would help - just do an Auto-Scan - you can do a dry-run without actual VCDS here --> Ross-Tech: VCDS Tour

The Scan should report what's not working electrically - disconnects, failed sensors, etc. - under Address 10: Park/Steer Assist
A few fault codes here --> https://t6forum.com/threads/vcds-and-carista-fault-codes.14143/post-231838

The actual sensors can be interrogated using function "Advanced Measurement Values" (VCDS > Select Control Module > 10-Park/Steer Assist > Adv. Meas. Values

EDIT:

T5.1: black 10-pin connector under left seat - actually the same in T6.
Thanks, going to get the VCDS working ASAP.

This connector under the seat. Do you mean like the one in the rear quarter panel like Bob shows on post 4 here? >> faulty-rear-parking-sensors.4740

The reason I ask is that I can't see anything like that under the seat. You do mean under left seat on UK van?

Thanks.
 
Last edited:
This connector under the seat. is it like the one in the rear quarter panel like Bob shows on post 4 here> faulty-rear-parking-sensors.4740The reason I ask is that I can't see anything like that.
The connector is similar to the red, green, grey? connectors in your picture - just black (perhaps hiding behind the green in the picture).
You do mean under left seat on UK van?
Yes, under left seat (your passenger seat) - actually/fortunately these are the same on LHD and RHD.
 
The connector is similar to the red, green, grey? connectors in your picture - just black (perhaps hiding behind the green in the picture).

Yes, under left seat (your passenger seat) - actually/fortunately these are the same on LHD and RHD.
Found it! Thank you

Its a little tucked out of the way where the converters have put it! I have managed to get a finger to it and push the wires around with it in reverse gear and the sensors didn't sping into action, so I guess I'll continue with loading windows and try the VCDS :rolleyes:
 
  • Like
Reactions: mmi
Certainly would help - just do an Auto-Scan - you can do a dry-run without actual VCDS here --> Ross-Tech: VCDS Tour
It didn’t go so well!

Got the laptop sorted with windows and the VCDS operating and then the laptop gave out on me :(

Just before it went off I managed to read on the screen, but not save, Rear left parking aid sensor (or similar) and Open/Short to Ground. Does 'Rear left' mean what I think of as the left? So far N/S sensor, not second one in!

another thing that doesn’t make sense here, everything I read says sensors should make a chirping noise. If only one has failed why do I get no noise from any?


The actual sensors can be interrogated using function "Advanced Measurement Values" (VCDS > Select Control Module > 10-Park/Steer Assist > Adv. Meas. Values
And before I had a little play with this, I got as far as a pop up window with lots of choices and tick boxes on them. If I can get back into it what do I do from there?
 
Rear left parking aid sensor (or similar) and Open/Short to Ground. Does 'Rear left' mean what I think of as the left? So far N/S sensor, not second one in!
Yes, the sensors:
Rear Left Parking Aid Sensor​
Center Rear Left Parking Aid Sensor​
Center Rear Right Parking Aid Sensor​
Rear Right Parking Aid Sensor​
lots of choices and tick boxes on them. If I can get back into it what do I do from there?
Browse through the choices and tick the "right" ones - the selected will be copied to the measurement screen and the actual values come alive right away.

You could expedite the search by typing in part of the name (e.g. "rear" on top line (as below "distance") - only selections containing the string will show up.
1626846755050.png1626847125191.png
Then either
1) just observe, or
2) save a snapshot (into log file), or
3) log selected measurements (into a .CSV-formatted (Excel) log-file) - to create a time stamped event file (probably not needed here)
 
Yes, the sensors:
Rear Left Parking Aid Sensor​
Center Rear Left Parking Aid Sensor​
Center Rear Right Parking Aid Sensor​
Rear Right Parking Aid Sensor​

Browse through the choices and tick the "right" ones - the selected will be copied to the measurement screen and the actual values come alive right away.

You could expedite the search by typing in part of the name (e.g. "rear" on top line (as below "distance") - only selections containing the string will show up.
View attachment 124364View attachment 124365
Then either
1) just observe, or
2) save a snapshot (into log file), or
3) log selected measurements (into a .CSV-formatted (Excel) log-file) - to create a time stamped event file (probably not needed here)
many thanks one again. if I can ever get it working again I know what to do now.
 
Does anybody know if I take the (apparent) offending sensor away should the others would then click?
 
Thanks pauly

So is it only if the 'actual' sensor itself is faulty that the others will make the clicking sounds? I must say I haven't experienced this noise on any sensors I've tried listening to yet, and starting to wonder if it's a figment of somebodies imagination, either that or my OLD ears :rolleyes:
 
So is it only if the 'actual' sensor itself is faulty that the others will make the clicking sounds? I must say I haven't experienced this noise on any sensors I've tried listening to yet, and starting to wonder if it's a figment of somebodies imagination, either that or my OLD ears
Yes, it's very difficult to hear (I can't hear either) without any helping tool - an old-school automotive stethoscope would be extremely helpful. Also by touching the surface very gently with your fingernail makes the sound somewhat audible.
EDIT: Actually a flat headed metal pin works very well - just touch gently the sensor.
EDIT_2: I just had to made a recording using an automotive stethoscope touching middle of T6 rear left PDC sensor - Woodpecker at 9.4 Hertz.
View attachment T6_rear_left_PDC_sensor.mp3
EDIT_3: Note to myself - the PDC above was 1K8 919 472 C, however the sensor is OEM T6 sensor. Need to verify using original 7E0 919 475 AA.
 
Last edited:
Yes, it's very difficult to hear (I can't hear either) without any helping tool - an old-school automotive stethoscope would be extremely helpful. Also by touching the surface very gently with your fingernail makes the sound somewhat audible.
EDIT: Actually a flat headed metal pin works very well - just touch gently the sensor.
EDIT_2: I just had to made a recording using an automotive stethoscope touching middle of T6 rear left PDC sensor - Woodpecker at 9.4 Hertz.
View attachment 124419
Wow that's amazing the amplification you cab get.

I wonder if the microphone of a mobile phone would have the same effect!
 
Back
Top