Checking steering-angle sensor

→ After working on wheel suspension parts, when replacing the steering-angle sensor, and after changing the wheel alignment values, calibrate the steering-angle sensor using PIWIS Tester 3 9900  .

→ Keep the front wheels in straight-ahead position on the measuring platform during calibration.

→ For vehicles with electromechanical steering, also re-teach the electric steering lock settings.

→ Prior to disconnecting the control unit, switch off the ignition and remove the ignition key.

→ Ensure that the power supply is not interrupted during programming.

→ Connect a battery charger with a current rating of at least → Nominal value: 40 A  to the vehicle battery.

Information 

• The steering-angle sensor is integrated into the steering column switch and records the movements of the steering wheel (steering wheel angle). The data is transmitted to the PSM control unit via the CAN bus  .
• During initialization, the steering-angle sensor learns its current position (straight-ahead position)  .
• Calibration must be performed when working on or carrying out subsequent work on the chassis  . This is described in detail in → 456005 INITIALISING AND CALIBRATING STEERING-ANGLE SENSOR .
• The calibration results in zero point balancing (exactly straight ahead)  .
• The steering-angle sensor is calibrated when first fitted and when any work has been carried out on steering and chassis. Examples of this would be opening the steering wiring and alterations to toe and camber  .
• Calibration includes initialization  .

1. Turn wheels to straight-ahead position.
2. From the straight-ahead position, turn steering wheel approx. 6° to the left and 6° to the right (past straight-ahead position).

Following successful initialization, the stored fault code is set to "not present". The PSM indicator light in the instrument cluster goes out.