ESP System Function Test

From Ross-Tech Wiki


  • The ESP System Function or Road Test serves to check the Plausibility of the Signals
    from the Lateral Acceleration Sensor (G200), Rotation Rate Sensor (G202) and Brake Pressure Sensor (G201).
  • The ESP System Function Test should be performed after all major work on the Brake System, in some cases the Brake Electronics Control Module (J104) may automatically require this Function Test and set the correlating Fault Code 01486.
  • Once the Function Test has been started it cannot be cancelled and must be successfully finished.
  • The Diagnostic Tool should NOT need to be connected while performing the Function Test.

Registered customers can contact us directly via email for assistance completing the Function Test with a complete Auto-Scan and the repair history. Our Techs have vast experience with this Subject and will gladly assist you with the Process. ;-)


  • The ONLY fault that should be stored in the 03-ABS controller is 01486 and the 44-Steering Assist module should be fault-free.
  • VCDS should NOT need to be connected while performing the Function Test!
  • Vehicle stationary
  • Ignition ON, Engine ON (Running)
  • Perform the Test Drive on an enclosed Site (i.e. a Parking Lot)
  • Make sure to Complete the Function Test within 50 Seconds after pressing the Brake Pedal


  • Firmly press the Brake Pedal until a certain Brake Pressure (usually right above 30 bar) is reached.
  • Brake Pressure Sensor (G201) Plausibility will be confirmed by a Change in the Brake Electronics Warning Lights.
    • On Bosch, the ASR/ESP Warning Light (K155) will switch OFF and the ABS Warning Light (K47) will switch ON.
    • On Continental/Teves, the ABS Warning Light (K47) will switch OFF and the ASR/ESP Warning Light (K155) switch ON.
  • Start Driving straight with a steady Speed of ~20 km/h (~13 mph).
  • Turn the Steering Wheel either Left or Right between a 90° Angle (1/4 Turn) to 180° Angle (1/2 Turn) and keep it steady.
  • Lateral Acceleration Sensor (G200) and Rotation Rate Sensor (G202) Plausibility is confirmed
    once the remaining Brake Electronics Warning Light(s) switch OFF.
  • The Function Test is now completed.


  • When Driving, make sure the general Speed is between 15 to 30 kph (9 to 18 mph).
  • The Turn should be done at a Rotation/Turn Rate of ~10 °/s which can be achieved with a
    Turning Radius of 10 to 12 Meters (30 to 40 feet) with a Speed between 15 to 30 kph (9 to 18 mph).
  • You may experience Variations in the Warning Light Behavior depending on the individual Brake System Generation,
    this is no Reason to be concerned as long as you follow the General Procedure.

Video Link

Systemfuntiontest screengrab.jpg