ELECTRONICALLY CONTROLLED BRAKE SYSTEM Brake Hold Standby Indicator Light Circuit

DESCRIPTION

The brake hold standby indicator light turns on if brake hold control is possible when the following conditions required for operation standby are met and the brake hold switch is turned on while the engine switch is on (IG).


WIRING DIAGRAM

Figure 1. for RHD:

B000W2SE02

Figure 2. for LHD:

B000W2SE01

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU assembly, perform initialization and calibration of the linear solenoid valve.

Click here

PROCEDURE


  1. PRE-CHECK


    1. If the brake hold standby indicator light does not illuminate even though the brake hold switch is pushed, check that the brake hold function operation conditions are met.


      1. The driver side door is closed.

      2. The driver side seat belt is fastened.

      3. The system is normal.

      Tech Tips

      If a malfunction occurs in one of the following systems, the brake hold operated indicator light will blink. If this occurs, perform troubleshooting on the malfunctioning system.


      • Brake system

      • Electric parking brake system

      • SFI system

      Result
      Proceed to
      NEXT

    NEXT
  2. CHECK CAN COMMUNICATION SYSTEM


    1. Check if CAN communication system DTCs are output.

      Click here

      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

    B
    A
  3. PERFORM ACTIVE TEST USING GTS (BRAKE HOLD STANDBY INDICATOR LIGHT)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Select the Active Test on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      BH Standby Light Brake hold standby indicator light Indicator light ON/OFF Observe combination meter assembly

      Chassis > ABS/VSC/TRC > Active Test
      Tester Display
      BH Standby Light
    4. Select the Data List on the GTS.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      BH Standby Light Brake hold standby indicator light ON or OFF

      ON: Indicator light on

      OFF: Indicator light off

      -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      BH Standby Light
    5. Check the operating condition of the brake hold standby indicator light when operating it using the GTS.

      Result
      Result Proceed to
      Brake hold standby indicator light in the Data List does not change using the Active Test. A
      Brake hold standby indicator light in the Data List turns ON/OFF using the Active Test. B

    A
    B
  4. INSPECT COMBINATION METER ASSEMBLY


    1. Turn the engine switch off.

    2. Perform the Active Test of the combination meter assembly (meter CPU) using the GTS.

      Click here


      Body Electrical > Combination Meter > Active Test
      Tester Display
      Indicat. Brake Hold
    3. Check the combination meter assembly.

      OK
      The brake hold standby indicator light turns on or off in accordance with the GTS operation.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  5. INSPECT BRAKE HOLD SWITCH


    1. B000VOCC01
      *a

      Component without harness connected

      (Brake Hold Switch)

      Turn the engine switch off.

    2. Disconnect the P2 brake hold switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3 (+B) - 4 (E) Switch pushed Below 1 Ω
      3 (+B) - 4 (E) Switch not pushed 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG
    OK
  6. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU ASSEMBLY - BRAKE HOLD SWITCH)


    1. Disconnect the A10 skid control ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A10-14 (HZRI) - P2-3 (+B) Always Below 1 Ω
      A10-14 (HZRI) or P2-3 (+B) - Body ground Always 10 kΩ or higher
      P2-4 (E) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  7. INSPECT COURTESY LIGHT SWITCH


    1. Turn on the interior lights and check that they illuminate, and then set the switch so that the lights illuminate when the door is opened.

    2. Check that the lights illuminate when the driver side door is opened.

      OK
      The interior lights illuminate when the driver side door is opened.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  8. CHECK HARNESS AND CONNECTOR (CTY TERMINAL)


    1. B000YVCC08
      *a

      Component with harness connected

      (Skid Control ECU Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A8-14 (CTY) - Body ground Driver door open Below 1 V
      A8-14 (CTY) - Body ground Driver door closed Pulse generation (waveform 1)

      1. B000YV4C02
        *a Driver door closed
        *b Driver door open

        Waveform 1 (Reference)

        Item Content
        Tester Connection A8-14 (CTY) - Body ground
        Tool Setting 5 V/DIV., 10 ms./DIV.
        Vehicle Condition Driver door closed → open
      Result
      Proceed to
      OK
      NG

    OK
    NG