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Check Brake Override System

WARNING: Perform this test in a location where the driving can be checked safely, while paying sufficient attention to the vicinity. While driving, the traffic laws and regulations such as speed limit must always be observed.
  1. CHECK DTC. 
    1. Turn the ignition switch to OFF.
    2. Connect the Subaru Select Monitor to data link connector.
    3. Turn the ignition switch to ON.
    4. Turn the Subaru Select Monitor 4 to ON.
    5. Check the DTCs of the system that may be output.
      NOTE: Read the DTC using Subaru Select Monitor. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .

    Is there any DTC output?

    Yes  : Check DTC using "Diagnostic Trouble Code (DTC)". Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

    No  : Go to  2.

  2. READ DATA MONITOR. 

    Using the Subaru Select Monitor, read the value in [Stop Light Switch].

    NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .

    Is the value of [Stop Light Switch] changed to ON/OFF on the data monitor?

    Yes  : Go to  3.

    No  : Check the stop light circuit.

  3. CHECK BRAKE PEDAL. 

    Check the brake pedal. Ref. to BRAKE>BRAKE PEDAL>INSPECTION .

    Is the brake pedal OK?

    Yes  : Go to  4.

    No  : Adjust or replace the brake pedal. Ref. to BRAKE>BRAKE PEDAL .

  4. READ DATA MONITOR. 

    Using the Subaru Select Monitor, read the values in [Accelerator Pedal Pos.#1] and [Accelerator Pedal Pos.#2] when operating the accelerator pedal from fully closed to fully open.

    NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .

    Does the values of [Accelerator Pedal Pos.#1] and [Accelerator Pedal Pos.#2] continuously change?

    Yes  : Go to  5.

    No  : Replace the accelerator pedal. Ref. to SPEED CONTROL SYSTEMS (H4DOTC)>ACCELERATOR PEDAL .

  5. READ DATA MONITOR. 

    Using Subaru Select Monitor, read the value of [Vehicle Speed] when driving at a constant speed of 16.1 Km/h (10 MPH) or 64.4 Km/h (40 MPH).

    WARNING: During the driving test, the traffic laws and regulations such as speed limit must always be observed.
    NOTE: Use of the data storage function of Subaru Select Monitor allows the data during driving to be stored. The stored data can be checked after the driving.

    Does the value of [Vehicle Speed] change widely?

    Yes  : Check the combination meter. Ref. to INSTRUMENTATION/DRIVER INFO>COMBINATION METER .

    No  : In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.

    NOTE:
    • The value of [Accel. Opening Angle] on the data monitor normally changes according to the value of accelerator sensor No. 1 voltage ratio. (The values do not become the same. For values, refer to Data monitor.)
    • Even if the voltage difference between [Accel. Opening Angle] and the accelerator sensor No. 1 is large and the value of [Accel. Opening Angle] is not consistent, the corresponding control can be considered to be activated if the value of the accelerator sensor No. 1 voltage ratio is consistent. (Use of the data storage function of Subaru Select Monitor 4 allows the data during driving to be stored. The stored data can be checked after the driving.)
    • When the customer complains of deceleration feeling when he/she intentionally depresses both the accelerator pedal and the brake pedal, advise them not to depress both pedals. (Example: operating the brake pedal with the left foot while operating the accelerator pedal)