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Home >> Infiniti >> 2017 >> QX80 Base, RWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Drivers Assistance Systems - ADAS >> Driver Assistance System (ADAS Control Unit) (Introduction, Wiring Diagrams And Basic Inspection) >> DTC/Circuit Diagnosis >> C1A05 Brake SW/Stop Lamp SW >> ADAS Control Unit >> Diagnosis Procedure
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Diagnosis Procedure

  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 ICC BRAKE 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  8.

  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  14.

    NO 

    GO TO STEP  9.

  4. CHECK ICC SWITCH INSTALLATION

    1. Turn ignition switch OFF.
    2. Check ICC brake switch for correct installation. Refer to INSPECTION AND ADJUSTMENT .

    Is the inspection result normal?

    YES 

    GO TO STEP 5. 

    NO 

    Adjust ICC brake switch installation. Refer to INSPECTION AND ADJUSTMENT .

  5. ICC BRAKE SWITCH INSPECTION

    1. Disconnect ICC brake switch connector.
    2. Check ICC brake switch. Refer to COMPONENT INSPECTION (ICC BRAKE SWITCH) .

    Is the inspection result normal?

    YES 

    GO TO STEP 6. 

    NO 

    Replace ICC brake switch.

  6. CHECK ICC BRAKE SWITCH POWER SUPPLY CIRCUIT

    1. Turn the ignition switch ON.
    2. Check voltage between ICC brake switch harness connector and ground.
      Terminals Voltage
      (Approx.)
      (+) (-)
      ICC brake switch Ground
      Connector Terminal
      E68 1 Battery voltage

    Is the inspection result normal?

    YES 

    GO TO STEP 7. 

    NO 

    Repair the harnesses or connectors.

  7. CHECK HARNESS BETWEEN ICC BRAKE SWITCH AND ECM

    1. Turn ignition switch OFF
    2. Disconnect ECM connector.
    3. Check for continuity between ICC brake switch harness connector and ECM harness connector.
      ICC brake switch ECM Continuity
      Connector Terminal Connector Terminal
      E68 2 E20 140 Existed
    4. Check for continuity between ICC brake switch harness connector and ground.
      ICC brake switch Ground Continuity
      Connector Terminal
      E68 2 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 8. 

    NO 

    Repair the harnesses or connectors.

  8. PERFORM SELF-DIAGNOSIS OF ECM

    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 "ENGINE". 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

    1. Turn the ignition switch ON.
    2. Check voltage between stop lamp switch harness connector and ground.
      Terminals Voltage
      (Approx.)
      (+) (-)
      Stop lamp switch Ground
      Connector Terminal
      E115 1 Battery voltage
      3

    Is the inspection result normal?

    YES 

    GO TO STEP 12. 

    NO 

    Repair the harnesses or connectors.

  12. CHECK HARNESS BETWEEN STOP LAMP SWITCH AND ECM

    1. Turn ignition switch OFF
    2. Disconnect ECM, rear combination lamp and high-mounted stop lamp connectors.
    3. Check for continuity between stop lamp switch harness connector and ECM harness connector.
      Stop lamp switch ECM Continuity
      Connector Terminal Connector Terminal
      E115 2 E20 139 Existed
    4. Check for continuity between stop lamp switch harness connector and ground.
      Stop lamp switch Ground Continuity
      Connector Terminal
      E115 2 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 13. 

    NO 

    Repair the harnesses or connectors.

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

    1. Disconnect ABS actuator and electric unit (control unit) connector and resistor.
    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
      E115 4 E36 17 Existed
    3. Check for continuity between stop lamp switch harness connector and ground.
      Stop lamp switch Ground Continuity
      Connector Terminal
      E115 4 Not existed

    Is the inspection result normal?

    YES 

    GO TO STEP 14. 

    NO 

    Repair the harnesses or connectors.

  14. PERFORM SELF-DIAGNOSIS OF ECM

    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 "ENGINE". 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 15. 

  15. 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 

    Repair the ADAS control unit. Refer to REMOVAL AND INSTALLATION .

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