VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C120B

DTC Code DTC Name
C120B IG Supply Voltage Low

DESCRIPTION

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C120B

IG Supply Voltage Low

Master cylinder pressure sensor power supply voltage decrease occurs or history of voltage decrease exists, and defective master cylinder pressure sensor output continues for 1 second or more.

  • Master cylinder pressure sensor output defective

  • Skid control ECU (Brake actuator assembly)

  • ABS NO. 2 fuse

WIRING DIAGRAM

Refer to DTC C1241.

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CAUTION / NOTICE / HINT

Note:

  • When replacing the skid control ECU (brake actuator assembly), perform zero point calibration.

    Click here

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

PROCEDURE

  1. CHECK HARNESS AND CONNECTOR (+BS TERMINAL)

    1. C342353C24

      *a

      Front view of wire harness connector

      (to Skid Control ECU [Brake Actuator Assembly])

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

    2. Disconnect the A80 skid control ECU (brake actuator assembly) connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      A80-38 (+BS) - Body ground

      Always

      11 to 14 V

      A80-38 (+BS) - A80-25 (GND1)

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)

    OK

  2. RECONFIRM DTC

    1. Reconnect the A80 skid control ECU (brake actuator assembly) connector.

    2. Clear the DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    3. Check if the same DTC is recorded.

      Click here

      Chassis > ABS/VSC/TRC > Trouble Codes

    Result

    Result

    Proceed to

    DTC C120B is not output.

    A

    DTC C120B is output.

    B
    A

    USE SIMULATION METHOD TO CHECK

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    B

    REPLACE BRAKE ACTUATOR ASSEMBLY

    Click here