Input signal check



Use the procedures below to check whether the sensor and switch signals are sent to the acoustic vehicle alerting-ECU normally.
note
  • Prior to operation, check the system by using the AVAS-OFF indicator and confirm that no bulb is blown and no malfunction is present inside the acoustic vehicle alerting-ECU.(Refer to .)
  • Prior to this input signal check, the engine must be stopped.




  1. Within 18 seconds after the electric motor switch is turned ON, perform the following operations:

    1. Stop the vehicle.
    2. Release the brake pedal.
    3. Move the selector lever to P position.
    4. Using the special tool diagnosis code check harness (MB991529), earth diagnosis connector terminal No. 1 (diagnosis control terminal).
  2. Perform the operations below to activate the system.
    note
    • If step 2 is not performed within 30 seconds after step 1, or step 2 is not performed correctly, repeat from step 1.
    • If any of the following operations are performed in standby, repeat from step 1.

    1. Turn off the power supply mode of the electric motor switch.
    2. Drive the vehicle.
    3. Turn ON the AVAS switch.
    4. Remove the earth path for the diagnosis connector.

    1. Depress the brake pedal.
    2. Operate the parking switch and move the selector lever from P to N, P, N and P positions.
    3. Stop lamp switch: ON (brake pedal is depressed → OFF (brake pedal is released) → ON → OFF → ON → OFF
  3. While the system is active, the acoustic vehicle alerting speaker will remain sounding and the AVAS-OFF indicator will remain flashing. If the speaker does not sound or the indicator does not flash, perform the troubleshooting. (Refer to .)
  4. When any of the operations below is carried out, the speaker will stop sounding and the indicator will stop flashing.

    1. 30 seconds have elapsed since the system is activated.
    2. Turn off the power supply mode of the electric motor switch.
    3. Drive the vehicle.
    4. Remove the earth path for the diagnosis connector.