Wheel Sensor Problems

Caliconfidential · Sep 8, 2024

Hi all,

I am hoping someone can help with a problem I have with the root cause being the wheel sensor or wiring ( i think!).

1 - A few months ago i got notification on the dashboard of a low pressure in the front nearside tyre. I checked it and it was the correct PSI. This problem went away by itself for a couple of months.
2 - In August I got a much more serious message that there was a tyre pressure problem and an accompanying ABS / start-stop error. I don't know if ABS was working or not but start-stop was definitely disabled.
3 - I replaced the wheel sensor with a new Bosch part from autodoc. I didn't clear codes or anything as i do not have that equipment. The problem went away and start-stop was working.
4 - 3 days later the problem came back making me think the error was not the sensor but the wiring.
Is my reasoning correct and any suggestions on what to do next?

Many thanks in advance !!

secret lemonade drinker · Sep 8, 2024

You need to read the obd code to understand the nature of the fault.
I don't think a T5 has a Tyre Pressure Monitoring System with transmitters in each wheel, I believe the tyre pressure warning light is triggered by the ABS sensor detecting an abnormal rotation speed due to under or over inflation (normally).
The obd code will either be an ABS sensor implausible reading or No reading. either way these are stored in the ABS module of the ECU and would need to be cleared after the new sensor was installed.
However there is another part of the system you have not considered, the sensor is a magnetic hall effect transmitter working or reading the pulses of the stepped ring spinning on the hub, these are made of iron and can degrade, if some rust has clogged some of the steps this can cause an implausible reading, however replacement or cleaning is a real pain in the arse.
Either way you need an OBD reader to read the fault, reset the module and proceed further.

WelshGas · Sep 8, 2024

Caliconfidential said:
Hi all,

I am hoping someone can help with a problem I have with the root cause being the wheel sensor or wiring ( i think!).

1 - A few months ago i got notification on the dashboard of a low pressure in the front nearside tyre. I checked it and it was the correct PSI. This problem went away by itself for a couple of months.
2 - In August I got a much more serious message that there was a tyre pressure problem and an accompanying ABS / start-stop error. I don't know if ABS was working or not but start-stop was definitely disabled.
3 - I replaced the wheel sensor with a new Bosch part from autodoc. I didn't clear codes or anything as i do not have that equipment. The problem went away and start-stop was working.
4 - 3 days later the problem came back making me think the error was not the sensor but the wiring.
Is my reasoning correct and any suggestions on what to do next?

Many thanks in advance !!

As above, but commonly if you have one ASB sensor fail then there is an increased probability of others failing.
You really need the diagnostic codes read. VW could charge upto £150 to do this or buy a Carista module and download the app. It’s a subscription based service to read and reset diagnostic codes. Subscription from 1 month to 1 year