CANBUS Spew

[LiFers]

Afternoon,

Pulled up at traffic lights. Auto-brake engaged, Start/Stop activated, car immediately restarted, and every error in the book came up one by one.

Scan shows:
Control unit: 01 Engine
U112300 - Databus error value received
U041500 - Invalid Data Received From Anti-Lock Brake System Control Module (x2)

Control unit: 03 Brakes
C101D07 - Right rear ABS wheel speed sensor mechanical malfunction
C101D29 - Right rear ABS wheel speed sensor Implausible signal
C10E129 - Parking brake motors Implausible signal
C114602 - Tire pressure monitoring display Signal error
C10E2F0 - Control module for electro-mechanical parking brake Wheel speed sensor implausible signal

Control unit: 13 Adaptive Cruise Control
C10DF00 - Brake temperature
U112300 - Databus error value received (x6)
C110BF0 - Adaptive cruise control sensor Restricted view
C10C200 - Function restriction
B10E7F0 - Cruise Control Front Distance Range Sensor separated

Control unit: 22 All Wheel Control
Control unit: 2B Steering Column Lock
Control unit: 44 Steering Assistance
Control unit: 76 Parking Assistance
(all above have)
U112300 - Databus error value received

My guess would be that one sensor or wire or control module has gone bad and is putting out garbage data, anyone seen something like this before and have any ideas?

Also, anyone know good VW/Euro specialists in Sydney who aren't just going to replace modules and sensors until they find the broken one and then bill me for all of it?

[Lucas_R]

How old is your battery? If the battery is on its last legs then all sorts of weird electrical gremlins pop up.

Where in Sydney are you, in order to try and recommend a VW specialist to help diagnose?

[LiFers]

About a yr old. Replaced with a good AGM and S/S has been working great since. Usually S/S shows different behaviour as the battery starts to go bad.

[LiFers]

A bad wheel speed sensor can cause and ABS or traction control warning light as well as causing some speedometer issues.

With the help of the ABS speed sensors, the Tire Pressure Monitoring System (TPMS) compares the speed and rolling circumference of the in‐dividuals wheels.

It seems there's a different ABS speed sensor for vehicles with adaptive cruise control and electronic parking brakes, so a guess would say that a faulty sensor could cause issues in most of the systems mentioned in the scan. I think I'm going to unplug it and clear the faults and see if all the 'error value received' messages go away and are just replaced with faults that the sensor is missing or failed, and then arrange to replace it.

[Lucas_R]

Hopefully one of the resident VW electrical gurus will chime in with their thoughts for you. Im pretty good mechanically, but with electronics I have no interest so I can only offer so much advice.

[LiFers]

For some reason I didn't think of it before, but I ran the live data for ABS Speed Sensors for all four wheels, and three of them are registering the correct speed, but the right rear sensor is not. Ordering a replacement and hopefully don't find that it's a damaged cable or similar when I get the car up on a hoist.

[Lucas_R]

For some reason I didn't think of it before, but I ran the live data for ABS Speed Sensors for all four wheels, and three of them are registering the correct speed, but the right rear sensor is not. Ordering a replacement and hopefully don't find that it's a damaged cable or similar when I get the car up on a hoist.

Actually the speed sensors failing are a somewhat common issue on the Mk7’s, so chances are thats your problem given one of them is not giving a reading.