DYNAMIC TORQUE CONTROL AWD SYSTEM, Diagnostic DTC:C120C/79

DTC Code DTC Name
C120C/79 Linear Solenoid Power Supply System Malfunction

DESCRIPTION

This DTC is output by the 4WD ECU assembly if a malfunction occurs in the linear solenoid power supply system.

DTC No. Detection Item DTC Detection Condition Trouble Area
C120C/79 Linear Solenoid Power Supply System Malfunction

  1. When the 4WD relay is on, the 4WD relay monitor remains off for 1 second or more while the voltage at the IG1 terminal is 9.5 V or more

  2. When the 4WD relay is on, the 4WD relay monitor remains off for 1 second or more while the voltage at the IG1 terminal is less than 9.5 V

  3. While the 4WD relay is off, the 4WD relay monitor remains on for 1 second or more immediately after the engine switch is turned on (IG)

  • Wire harness and connector (IG1 circuit, GND circuit)

  • 4WD ECU assembly

WIRING DIAGRAM

B008HRRE08
*a from IG1 Circuit
*b ECU-IG NO. 6
*c 4WD ECU Assembly

CAUTION / NOTICE / HINT

Note


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

  • When the 4WD ECU assembly is replaced with a normal one from another vehicle, it is necessary to perform calibration.

    Click here

Tech Tips

Check the condition of each related circuit connector before troubleshooting.

Click here

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)


    1. B008I8KC47
      *a

      Front view of wire harness connector

      (to 4WD ECU Assembly)

      Disconnect the I55 4WD ECU assembly connector.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      I55-3 (IG1) -Body ground Engine switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK HARNESS AND CONNECTOR (GND TERMINAL)


    1. Turn the engine switch off.

    2. B008I8KC48
      *a

      Front view of wire harness connector

      (to 4WD ECU Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I55-4 (GND) -Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. RECONFIRM DTC


    1. Reconnect the I55 4WD ECU assembly connector.

    2. Clear the DTCs.

      Click here


      Chassis > Four Wheel Drive > Clear DTCs

    3. Turn the engine switch off.

    4. Turn the engine switch on (IG).

    5. Check that no DTCs other than DTC C120C/79 have been output.

      Click here


      Chassis > Four Wheel Drive > Trouble Codes
      Result
      Proceed to
      DTCs other than C120C/79 are not output
      DTCs other than C120C/79 are output

    DTCs other than C120C/79 are not output

    REPLACE 4WD ECU ASSEMBLY for LHD: Click here
    REPLACE 4WD ECU ASSEMBLY for RHD: Click here

    DTCs other than C120C/79 are output

    REPAIR CIRCUIT INDICATED BY OUTPUT CODE Click here