PRE-COLLISION SYSTEM, Diagnostic DTC:C1A4B

DTC Code DTC Name
C1A4B Stop Light Relay Circuit

DESCRIPTION

The skid control ECU (brake booster with master cylinder assembly) sends a stop light operation request signal to the stop light relay (stop light control ECU assembly). If the skid control ECU (brake booster with master cylinder assembly) detects a malfunction in the stop light relay (stop light control ECU assembly) circuit, the driving support ECU assembly stores DTC C1A4B.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1A4B Stop Light Relay Circuit

Both of the following conditions are met:


  1. All of the following conditions are met:


    • 3 seconds have elapsed since the power switch was turned to on (IG).

    • The auxiliary battery voltage is 10 V or more for 3 seconds or more.

  2. All of the following conditions are met for 1 second or more:


    • Communication between the driving support ECU assembly and skid control ECU (brake booster with master cylinder assembly) is normal.

    • The driving support ECU assembly receives a stop light relay circuit malfunction signal from the skid control ECU (brake booster with master cylinder assembly)

Tech Tips

The skid control ECU (brake booster with master cylinder assembly) will detect a stop light relay circuit malfunction if any of the following conditions are met:


  • When the voltage at the IG1 terminal is between 11 V and 14 V and the stop light illumination output (STPO) signal is on, a signal has not been input to the STP terminal continuously for 2 seconds or more.

  • When the voltage at the IG1 terminal is between 11 V and 14 V and the stop light illumination output (STPO) signal is off, the input signals at the STP terminal and STP2 terminal differ continuously for 5 seconds or more.


  • Skid control ECU (Brake booster with master cylinder assembly)

  • Stop light relay (Stop light control ECU assembly)

  • Vehicle Approaching Speaker Controller

  • Rear combination light assembly LH

  • Rear combination light assembly RH

  • Rear light assembly LH

  • Rear light assembly RH

  • Center stop light assembly

  • No. 4 antenna cord sub-assembly (w/ Radio Antenna)

  • Noise filter (w/ Radio Antenna)

  • Harness or connector

WIRING DIAGRAM

B001K8JE01

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • Make sure that there is no looseness at the locking part and the connecting part of the connector.

  • Check both the connector case and the terminals for deformation and corrosion.

PROCEDURE


  1. INSPECT TERMINAL VOLTAGE (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) CONNECTOR)


    1. Turn the power switch off.

    2. B001LV6C04
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Brake Booster with Master Cylinder Assembly))

      Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-6 (STP2) - Body ground Brake pedal depressed 11 to 14 V
      Brake pedal released Below 1.5 V
      A61-3 (STPO) - Body ground Always 11 to 14 V
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
      Brake pedal released Below 1.5 V
    4. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Result Proceed to
      The voltage is as specified for every terminal. A
      Only the voltage at terminal STP2 is not as specified. B
      Only the voltage at terminal STPO is not as specified. C
      Only the voltage at terminal STP is not as specified. D
      The voltage at both terminal STPO and terminal STP are not as specified. E

    B
    C
    D
    E
    A
  2. PERFORM ACTIVE TEST USING GTS (STOP LIGHT RELAY)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Chassis / ABS/VSC/TRC / Active Test.

    5. According to the display on the GTS, perform the Active Test Stop Light Relay.

      Click here

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Stop Light Relay Stop light relay (Stop light control ECU assembly) ON / OFF Stop lights come on
      OK
      The stop lights turn on and off correctly in response to the operation of the Active Test.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. CHECK FOR DTCS (PRE-COLLISION SYSTEM)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.

    5. Clear the DTCs.

      Click here

    6. Enter the following menus: Chassis / ABS/VSC/TRC / Active Test.

    7. According to the display on the GTS, perform the Active Test Stop Light Relay.

      Click here

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Stop Light Relay Stop light relay (Stop light control ECU assembly) ON / OFF Stop lights come on
    8. Enter the following menus: Body Electrical / Pre-Collision 2 / Trouble Codes.

    9. Check for DTCs.

      Click here

      OK
      DTC C1A4B is not output
      Result
      Proceed to
      OK
      NG

    OK
    NG
  4. INSPECT STOP LIGHT RELAY (STOP LIGHT CONTROL ECU ASSEMBLY)


    1. Inspect the stop light relay (stop light control ECU assembly).

      Click here

      OK
      The stop light relay (stop light control ECU assembly) is normal.
      Result
      Proceed to
      OK
      NG

    OK
    NG
  5. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - STOP LIGHT RELAY (STOP LIGHT CONTROL ECU ASSEMBLY))


    1. Turn the power switch off.

    2. Disconnect the A27 stop light relay (stop light control ECU assembly) connector.

    3. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A61-3 (STPO) - A27-9 (ACC) Always Below 1 Ω
    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    6. Connect the A27 stop light relay (stop light control ECU assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  6. INSPECT TERMINAL VOLTAGE (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) CONNECTOR)


    1. Turn the power switch off.

    2. B001LV6C05
      *a

      Front view of wire harness connector

      (to Skid Control ECU (Brake Booster with Master Cylinder Assembly))

      Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  7. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - VEHICLE APPROACHING SPEAKER CONTROLLER)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the H183 vehicle approaching speaker controller connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the H183 vehicle approaching speaker controller connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  8. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR COMBINATION LIGHT ASSEMBLY LH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the P22 rear combination light assembly LH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the P22 rear combination light assembly LH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  9. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR COMBINATION LIGHT ASSEMBLY RH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the Q15 rear combination light assembly RH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the Q15 rear combination light assembly RH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  10. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR LIGHT ASSEMBLY LH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the V16 rear light assembly LH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the V16 rear light assembly LH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  11. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR LIGHT ASSEMBLY RH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the V15 rear light assembly RH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the V15 rear light assembly RH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Result Proceed to
      OK A
      NG (w/o Radio Antenna) B
      NG (w/ Radio Antenna) C

    A
    C
    B
  12. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - CENTER STOP LIGHT ASSEMBLY)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the a1 center stop light assembly connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the a1 center stop light assembly connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  13. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - NOISE FILTER)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the P31 noise filter connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the P31 noise filter connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  14. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - CENTER STOP LIGHT ASSEMBLY)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the a1 center stop light assembly connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal depressed 11 to 14 V
    4. Connect the a1 center stop light assembly connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  15. CHECK WIRE HARNESS AND CONNECTOR (NO. 4 ANTENNA CORD SUB-ASSEMBLY - CENTER STOP LIGHT ASSEMBLY)


    1. Disconnect the a2 No. 4 antenna cord sub-assembly connector.

    2. Disconnect the a1 center stop light assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      a2-1 (B) - Body ground Always 10 kΩ or higher
      a1-2 (B2) - Body ground Always 10 kΩ or higher
    4. Connect the a1 center stop light assembly connector.

    5. Connect the a2 No. 4 antenna cord sub-assembly connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  16. INSPECT NOISE FILTER


    1. Disconnect the P31 and A noise filter connector.

      B001MXLC02
      *1 Noise Filter - -
      *a Component without harness connected - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      P31-1 (HMSL) - Body ground Always 10 kΩ or higher
      A-1 - Body ground Always 10 kΩ or higher
    3. Connect the P31 and A noise filter connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  17. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - STOP LIGHT RELAY (STOP LIGHT CONTROL ECU ASSEMBLY))


    1. Turn the power switch off.

    2. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    3. Disconnect the A27 stop light relay (stop light control ECU assembly) connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A27-5 (STP) - A61-6 (STP2) Always Below 1 Ω
      A27-1 (OUT) - A61-33 (STP) Always Below 1 Ω
      A27-1 (OUT) or A61-33 (STP) - Body ground Always 10 kΩ or higher
    5. Connect the A27 stop light relay (stop light control ECU assembly) connector.

    6. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  18. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - STOP LIGHT RELAY (STOP LIGHT CONTROL ECU ASSEMBLY))


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the A27 stop light relay (stop light control ECU assembly) connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the A27 stop light relay (stop light control ECU assembly) connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  19. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - VEHICLE APPROACHING SPEAKER CONTROLLER)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the H183 vehicle approaching speaker controller connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the H183 vehicle approaching speaker controller connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  20. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR COMBINATION LIGHT ASSEMBLY LH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the P22 rear combination light assembly LH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the P22 rear combination light assembly LH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  21. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR COMBINATION LIGHT ASSEMBLY RH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the Q15 rear combination light assembly RH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the Q15 rear combination light assembly RH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  22. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR LIGHT ASSEMBLY LH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the V16 rear light assembly LH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the V16 rear light assembly LH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  23. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - REAR LIGHT ASSEMBLY RH)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the V15 rear light assembly RH connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the V15 rear light assembly RH connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Result Proceed to
      OK A
      NG (w/o Radio Antenna) B
      NG (w/ Radio Antenna) C

    A
    C
    B
  24. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - CENTER STOP LIGHT ASSEMBLY)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the a1 center stop light assembly connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the a1 center stop light assembly connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  25. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - NOISE FILTER)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the P31 noise filter connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the P31 noise filter connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  26. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - CENTER STOP LIGHT ASSEMBLY)


    1. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    2. Disconnect the a1 center stop light assembly connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A61-33 (STP) - Body ground Brake pedal released Below 1.5 V
    4. Connect the a1 center stop light assembly connector.

    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  27. CHECK WIRE HARNESS AND CONNECTOR (NO. 4 ANTENNA CORD SUB-ASSEMBLY - CENTER STOP LIGHT ASSEMBLY)


    1. Disconnect the a2 No. 4 antenna cord sub-assembly connector.

    2. Disconnect the a1 center stop light assembly connector.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      a2-1 (B) - Body ground Always Below 1.5 V
      a1-2 (B2) - Body ground Always Below 1.5 V
    4. Connect the a1 center stop light assembly connector.

    5. Connect the a2 No. 4 antenna cord sub-assembly connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  28. INSPECT NOISE FILTER


    1. Disconnect the P31 and A noise filter connector.

      B001MXLC02
      *1 Noise Filter - -
      *a Component without harness connected - -
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      P31-1 (HMSL) - Body ground Always Below 1.5 V
      A-1 - Body ground Always Below 1.5 V
    3. Connect the P31 and A noise filter connector.

      Result
      Proceed to
      OK
      NG

    OK
    NG
  29. CHECK WIRE HARNESS AND CONNECTOR (SKID CONTROL ECU (BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY) - STOP LIGHT RELAY (STOP LIGHT CONTROL ECU ASSEMBLY))


    1. Turn the power switch off.

    2. Disconnect the A27 stop light relay (stop light control ECU assembly) connector.

    3. Disconnect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      A61-3 (STPO) or A27-9 (ACC) - Body ground Always 10 kΩ or higher
    5. Connect the A61 skid control ECU (brake booster with master cylinder assembly) connector.

    6. Connect the A27 stop light relay (stop light control ECU assembly) connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  30. INSPECT STOP LIGHT RELAY (STOP LIGHT CONTROL ECU ASSEMBLY)


    1. Inspect the stop light relay (stop light control ECU assembly).

      Click here

      OK
      The stop light relay (stop light control ECU assembly) is normal.
      Result
      Result Proceed to
      OK A
      NG (Stop light relay (stop light control ECU assembly)) B
      NG (Power source circuit or Body ground circuit) C

    A
    B
    C