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Home >> Infiniti >> 2017 >> Q60 Base, RWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Collision/Avoidance >> Driver Assistance System (ADAS Control Unit) (Introduction, Basic Diagnosis, DTC/Circuit Diagnosis) (1 Of 2) >> DTC/Circuit Diagnosis >> DTC C1A05: Brake SW/Stop Lamp SW >> ADAS Control Unit >> Diagnosis Procedure (2.0 Turbo Gasoline Engine)
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Diagnosis Procedure (2.0 Turbo Gasoline Engine)

  1. CHECK DTC PRIORITY

    If DTC "C1A05" is displayed with DTC "U1000", first diagnose the DTC "U1000".

    Is applicable DTC detected?

    YES 

    Perform diagnosis of applicable. Refer to DTC DESCRIPTION .

    NO 

    GO TO STEP 2  .

  2. CHECK STOP LAMP SWITCH AND BRAKE PEDAL POSITION SWITCH

    Check that "STOP LAMP SW" and "BRAKE SW" operate normally in "DATA MONITOR" of "ICC/ADAS".

    Is the inspection result normal?

    YES 

    GO TO STEP 3. 

    NO-1 

    When "BRAKE SW" operation is malfunctioning: GO TO STEP 4. 

    NO-2 

    When "STOP LAMP SW" operation is malfunctioning: GO TO STEP 9. 

  3. CHECK STOP LAMP SWITCH

    Check that "STOP LAMP SW" operate normally in "DATA MONITOR" of "ABS".

    Is the inspection result normal?

    YES 

    GO TO STEP 16. 

    NO 

    GO TO STEP 9. 

  4. CHECK BRAKE PEDAL POSITION SWITCH INSTALLATION

    1. Turn Ignition Switch OFF.
    2. Check brake pedal position Switch for correct installation. Refer to INSPECTION AND ADJUSTMENT .

    Is the inspection result normal?

    YES 

    GO TO STEP 5. 

    NO 

    Adjust brake pedal position Switch installation. Refer to INSPECTION AND ADJUSTMENT .

  5. BRAKE PEDAL POSITION SWITCH INSPECTION

    1. Disconnect brake pedal position Switch connector.
    2. Check brake pedal position Switch. Refer to COMPONENT INSPECTION (BRAKE PEDAL POSITION SWITCH) .

    Is the inspection result normal?

    YES 

    GO TO STEP 6. 

    NO 

    Replace brake pedal position Switch.

  6. CHECK BRAKE PEDAL POSITION SWITCH POWER SUPPLY CIRCUIT

    1. Turn the Ignition Switch ON.
    2. Check voltage between brake pedal position Switch harness connector and ground.
      Terminals Voltage
      (Approx.)
      (+) (-)
      Brake pedal position Switch Ground
      Connector Terminal
      E44 1 Battery voltage

    Is the inspection result normal?

    YES 

    GO TO STEP 7. 

    NO 

    Repair the harnesses or connectors.

  7. CHECK HARNESS BETWEEN BRAKE PEDAL POSITION SWITCH AND EMCM

    1. Turn Ignition Switch OFF
    2. Disconnect EMCM connector.
    3. Check for continuity between brake pedal position Switch harness connector and EMCM harness connector.
      Brake pedal position Switch EMCM Continuity
      Connector Terminal Connector Terminal
      E44 2 M147 23 Existed
    4. Check for continuity between brake pedal position Switch harness connector and ground.
      Brake pedal position Switch Ground Continuity
      Connector Terminal
      E44 2 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 8. 

    NO 

    Repair the harnesses or connectors.

  8. PERFORM SELF-DIAGNOSIS OF EMCM

    1. Connect all connectors again if the connectors are disconnected.
    2. Turn Ignition Switch ON.
    3. Perform "All DTC Reading".
    4. Check if any DTC is detected in "Self Diagnostic Result" of "EMCM". Refer to DTC INDEX .

    Is any DTC detected?

    YES 

    Repair or replace the malfunctioning parts identified by the self-diagnosis result.

    NO 

    Replace the ADAS Control Unit. Refer to REMOVAL AND INSTALLATION .

  9. CHECK STOP LAMP SWITCH INSTALLATION

    1. Turn Ignition Switch OFF.
    2. Check stop lamp Switch for correct installation. Refer to INSPECTION AND ADJUSTMENT .

    Is the inspection result normal?

    YES 

    GO TO STEP 10. 

    NO 

    Adjust stop lamp Switch installation. Refer to INSPECTION AND ADJUSTMENT .

  10. STOP LAMP SWITCH INSPECTION

    1. Disconnect stop lamp Switch connector.
    2. Check stop lamp Switch. Refer to COMPONENT INSPECTION (STOP LAMP SWITCH) .

    Is the inspection result normal?

    YES 

    GO TO STEP 11. 

    NO 

    Replace stop lamp Switch.

  11. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT

    Check voltage between stop lamp Switch harness connector and ground.

    Terminals Voltage
    (Approx.)
    (+) (-)
    Stop lamp Switch Ground
    Connector Terminal
    E57 1 Battery voltage
    3

    Is the inspection result normal?

    YES 

    GO TO STEP 12. 

    NO 

    Repair the harnesses or connectors.

  12. CHECK STOP LAMP SWITCH INPUT SIGNAL

    Check the voltage between BCM harness connector and ground.

    Terminals Voltage
    (Approx.)
    (+) (-)
    BCM Ground
    Connector Terminal
    M13 25 Battery voltage

    Is the inspection result normal?

    YES 

    GO TO STEP 13. 

    NO 

    Repair the harnesses or connectors.

  13. CHECK HARNESS BETWEEN STOP LAMP SWITCH AND BCM

    1. Turn Ignition Switch OFF
    2. Check for continuity between stop lamp Switch harness connector and BCM harness connector.
      Stop lamp Switch BCM Continuity
      Connector Terminal Connector Terminal
      E57 4 M13 27 Existed
    3. Check for continuity between stop lamp Switch harness connector and ground.
      Stop lamp Switch Ground Continuity
      Connector Terminal
      E57 4 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 14. 

    NO 

    Repair the harnesses or connectors.

  14. CHECK HARNESS BETWEEN STOP LAMP SWITCH AND ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)

    1. Disconnect ABS actuator and electric unit (Control Unit) connector.
    2. Check for continuity between stop lamp Switch harness connector and ABS actuator and electric unit (Control Unit) harness connector.
      Stop lamp Switch ABS actuator and electric unit (Control Unit) Continuity
      Connector Terminal Connector Terminal
      E57 2 E35 5 Existed
    3. Check for continuity between stop lamp Switch harness connector and ground.
      Stop lamp Switch Ground Continuity
      Connector Terminal
      E57 2 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 15. 

    NO 

    Repair the harnesses or connectors.

  15. PERFORM SELF-DIAGNOSIS OF BCM

    1. Connect all connectors again if the connectors are disconnected.
    2. Turn Ignition Switch ON.
    3. Perform "All DTC Reading".
    4. Check if any DTC is detected in "Self Diagnostic Result" of "BCM". Refer to DTCINDEX .

    Is any DTC detected?

    YES 

    Repair or replace the malfunctioning parts identified by the self-diagnosis result.

    NO 

    GO TO STEP 16. 

  16. PERFORM SELF-DIAGNOSIS OF EMCM

    1. Connect all connectors again if the connectors are disconnected.
    2. Turn Ignition Switch ON.
    3. Perform "All DTC Reading".
    4. Check if any DTC is detected in "Self Diagnostic Result" of "EMCM". Refer to DTC INDEX .

    Is any DTC detected?

    YES 

    Repair or replace the malfunctioning parts identified by the self-diagnosis result.

    NO 

    GO TO STEP 17. 

  17. PERFORM SELF-DIAGNOSIS OF ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)

    Check if any DTC is detected in "Self Diagnostic Result" of "ABS". Refer to DTC INDEX .

    Is any DTC detected?

    YES 

    Repair or replace the malfunctioning parts identified by the self-diagnosis result.

    NO 

    Replace the ADAS Control Unit. Refer to REMOVAL AND INSTALLATION .

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