Cant give you any advice other than my history. Mine intermittently go off then will work again for a while. Then it will be another one or two going off! Nothing obvious like rain having an impact. I was advised by someone that camper conversions are notorious for this due to the running of the electric cabling clashing with the conversion power cabling but can find no referral to this on this forum. Another tip was use WD40 on the sensors but this fails as well. So frustrating
Try swapping the sensors round. If the fault moves then you have cracked it
The holding brackets for the rear parking sensors are very easily damaged. It is just about possible to remove the cable connector and parking sensor with the bumper in place but unlikely you’ll be able to refit them without removing the bumper.
I have an Intermittent fault with my reverse sensors on mybT6 Transporter. I have confirmed that all the actual sensors are working but switching them around and listening for them clicking / ticking etc. All four work but the drivers side corner sensor circuit has an intermitant issue . What I have found is when the fault is present I select reverse and I will get a long tone through the vehicle speakers and a message on the head unit that park pilot is not available.
After some fault finding I have worked out that if I put my multimeter on amps to measure the current draw between the pos wire on the sensor plug and the signal wire . (Pins 1 and 2 on the plug) the reverse sensors will start to work again . My thought is that the extra resistance that the multimeter adds to the circuit is enough to fix the fault . My plan is to a 10komh resistor in parallel between pins 1 and 2 on the reverse sensor plug with the hope it does the same job as the multimeter seems to do .
Has anyone else had a similar problem and tried this fix ?
After some fault finding I have worked out that if I put my multimeter on amps to measure the current draw between the pos wire on the sensor plug and the signal wire . (Pins 1 and 2 on the plug) the reverse sensors will start to work again . My thought is that the extra resistance that the multimeter adds to the circuit is enough to fix the fault . My plan is to a 10komh resistor in parallel between pins 1 and 2 on the reverse sensor plug with the hope it does the same job as the multimeter seems to do .
Has anyone else had a similar problem and tried this fix ?
The shunt to measure amps is very low resistance, usually milliohms, I doubt that's making a difference. I would think it more likely that by digging the probes in each side you are curing some sort of corrosion or bad contact issue.
The pins in the plug and on the sensor look very clean with no corrosion. I have cleaned them with contact cleaner a couple of times but it didn't make a difference
Also I can have the sensor unplugged completely and when I touch the probs across pins 1 and 2 with the meter set to amps a tone will come across the vehicle speakers and the fault will be cleared . I plug the sensor back in and they will work a few times then fail again
A multimeter set to amps is near as dammit just a wire, all you are doing in the second test is shorting the wires.
Potentially you might have a cable fault somewhere that handling the connections fixes for a while.
Potentially you might have a cable fault somewhere that handling the connections fixes for a while.
For sure I have considered the loose cable / connection option. I have removed the wiring loom from the bumper all the way to where it disappears behind the passengers side rear wheel arch and checked it in depth . I'm pretty sure it's not a loose connection that I'm remaking with the meter probs or handling the cables
So here is a video of the multimeter bringing the sensors back to life . You will see in the video that I have added a couple of resistors in parallel between pos and signal wires . This was just to test if it made a difference... it didn't so I removed them again but the multimeter trick works every time. Any ideas on what I can do to fix this problem
I don't disbelieve you that adding the multimeter seems to reset them for a while but it's not the resistance of the multimeter that's doing something here because there essentially is none, current shunts are extremely low resistance so they don't interfere with the measurements and the reading across them is a few millivolts.
I suspect you might get the same behaviour if you just briefly shorted the same connection.
My suspicion is that the fault is actually in the parking module, probably in whatever circuit they are using to buffer the input. I think by shorting that you are resetting something and then performance degrades over time.
Do you get fault codes when they fail?
I suspect you might get the same behaviour if you just briefly shorted the same connection.
My suspicion is that the fault is actually in the parking module, probably in whatever circuit they are using to buffer the input. I think by shorting that you are resetting something and then performance degrades over time.
Do you get fault codes when they fail?
I don't have a tool to read the fault codes unfortunately. The only error message given from the vehicle is the long tone when you select reverse and then a message on the headunit saying park pilot unavailable.
I am starting to think it is a faulty input on the control module also now . Maybe if I can find a pin out diagram I can swap the inputs from one of the other sensors to see if the fault transfers . What do you think ?
Do you know if the module located under the dash ?
I am starting to think it is a faulty input on the control module also now . Maybe if I can find a pin out diagram I can swap the inputs from one of the other sensors to see if the fault transfers . What do you think ?
Do you know if the module located under the dash ?
Module is under the dash. I’ve been having trouble with my rear parking too
If you take up the VIP Membership you have access to the wiring diagrams that will help you with pinouts. But to do any testing you are either going to have to repin the connectors or break into the wiring, which may introduce faults of it's own.
At this point I would have thought investing in one of the fault code solutions, or seeing if someone with one is nearby, is going to help more than patching around connectors.
At this point I would have thought investing in one of the fault code solutions, or seeing if someone with one is nearby, is going to help more than patching around connectors.
@brace4444 there is more info here.
www.t6forum.com
maybe one of the administrators/moderators could merge these threads?
Rear PDC problem
Started the van the other week and had the message on infotainment system show park assist not available and screen not showing anything from rear sensors. When I start up it beeps continuously for about 3 seconds then goes off and again nothing from the rear sensors. It’s a DSG T6. I plugged in...
maybe one of the administrators/moderators could merge these threads?
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Thanks . I will explore the diagnostic tool idea . Just something else that has come to my mind . My work vehicle is a 2022 VW Caddy with rear parking sensors , no front sensors or camera etc . Would the module on the Caddy and the Transporter be the same ? Can I swap them over and see if the fault transfers to the other veiche ??
New sensors are available on eBay, 4 for £20. Obviously not OEM but do the same job. Would be a quick and cheap test - I changed all mine without removing the bumper.
So, no joy with the snap-on or carista reader, so took a chance on a genuine replacement 2nd hand module. I’m still getting the same issue.
would you need to clear the fault after fitting new module? or like my thinking, that once the replacement is fitted it should autonatically start talking to the canbus properly?
guess I may need someone with VCDS to help me figure out what’s wrong
would you need to clear the fault after fitting new module? or like my thinking, that once the replacement is fitted it should autonatically start talking to the canbus properly?
guess I may need someone with VCDS to help me figure out what’s wrong
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