If you have access to VCDs I'd follow Ross-Techs advice before doing anything else.
00573 - Steering Torque Sensor (G269)
00573 - Steering Torque Sensor (G269): Implausible Signal
Possible Symptoms
Steering Assist not working
Possible Causes
Steering Assist Power Supply (Terminal 15) faulty
Wiring/Connectors from/to Steering Torque Sensor (G269) faulty
Steering Torque Sensor (G269) faulty
Possible Solutions
Check Steering Assist Power Supply (Terminal 15)
Check Fuse(s)
Check Wiring/Connectors from/to Steering Torque Sensor (G269)
Check Steering Torque Sensor (G269)
Special Notes
When found in VW Golf (1K) Steering Assist (and similar), check Steering Torque Sensor (G269)
Checking Steering Torque Sensor (G269)
Prerequisites:
Ignition ON
Engine ON (Idle)
System voltage at least 11.0 V.
[Select]
[44 - Steering Assist]
[Meas. Blocks - 08]
Group 001
[Go!]
Field 2: Steering Torque Sensor (G269)
Turn the Steering Wheel multiple times completely to the left and right. The Torque Values should change.
If the Torque Values do change, it's most likely an intermittent Fault in the Wiring/Connectors.
If the Torque Values do NOT change, the Sensor itself or the Power Supply (Terminal 15) might be faulty.
Group 004
[Go!]
Field 2: Power Supply (Terminal 15), Specification: "Term. 15 ON"
[Done, Go Back]
[Close Controller, Go Back - 06]