Volkswagen Electro-Mechanical Power Steering Warning Light Illuminated

Tech Tip: Volkswagen Electro-Mechanical Power Steering Warning Light Illuminated

The vehicle owner may be concerned because the battery was disconnected and now the Electro-Mechanical Power Steering Warning light is lit on the dash on a 2009 Volkswagen Eos Komfort 2.0L. This may be caused by an unprogrammed steering angle sensor (G85).

Vehicle: 2009 Volkswagen Eos Komfort 2.0L

Customer Concern: The battery was disconnected and now the Electro-Mechanical Power Steering Warning light is lit on the dash.

Potential Causes: Unprogrammed Steering Angle Sensor (G85)

Disconnected Battery Steering Limit Stop Basic Setting Procedure:


1. If the battery is disconnected, the basic settings for the Steering Angle Sensor G85 are lost. This will typically result in a trouble code 00778 – G85 Steering Angle Sensor Basic Settings lost in ABS.

2. Unlike earlier models with traditional hydraulic power steering systems, this vehicle is equipped with an electro-mechanical power steering system (large electric motor used to help steering vs. fluid).

3. In vehicles equipped with the electro-mechanical power steering, the G85 basic setting needs to be performed in the Steering Assist control module, not the ABS control ­module.

  a. If the vehicle is equipped with ESP, the G85 basic setting is still set in the ABS control ­­module.

4. Reset the G85 basic setting as follows:

  a. Start the vehicle and turn the steering wheel one turn to the right and one turn to the left.

  b. Drive a short distance in a straight line on a level surface. Stop with the wheels pointing straight.

  c. Leave the engine running and do not move the steering wheel.

  d. Select Address Word 44-Steering Assist.

  e. Select Function 11-Login or 16-Security Access. Enter a value of 40168.

  f. Select Function 04-Basic Settings. Enter Display Group 060. Activate the basic setting. The 1st Display Field should show “OK” when the setting has completed.

  g. Select Function 08-Read Measuring Value Blocks (MVB). Enter Display Group 007. The first Display Field should show a value between -1.5° and +1.5°.

5. After the G85 has been ­successfully set, the Steering Limit Stop adaptation needs to be performed. Loss of Steering Limit Stop Basic Setting will result in trouble code 02546 – Steering Limit Stop No or Incorrect Basic Setting/Adaptation – being stored.

6. Complete the Steering Limit Stop adaptation as follows:

  a. With the engine still running, center the steering wheel and hold it for five seconds.

  b. Turn the steering wheel completely to the left and hold it there for a second.

  c. Turn the steering wheel completely to the right and hold it there for a second.

  d. Center the steering wheel.

  e. Switch the engine and ignition off.

  f. Switch the ignition on and wait five ­seconds.

  g. The Steering Assist Warning Lamp should turn off. If it doesn’t, perform a short test drive.

Tech Tip: If the 02546 fault code does not clear out after the test drive, try repeating the procedure and increase the key cycle times to 30 ­seconds or more.

Courtesy of Identifix’s “Five Fast Fixes.”

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