ACTIVE HEIGHT CONTROL SUSPENSION, Diagnostic DTC:C1782

DTC Code DTC Name
C1782 Power Source Voltage Malfunction

DESCRIPTION

DTC Code Detection Condition Trouble Area
C1782 While the engine switch is on (IG), voltage at terminal IG, BAT and/or BAT2 is 10 V or less, or 16 V or more for 0.5 seconds.

  • Battery

  • Charging system

  • Harness or connector

  • AHC-B fuse

  • AHC-B No. 2 fuse

  • Suspension control ECU

WIRING DIAGRAM

B001W6BE02

CAUTION / NOTICE / HINT

Note


  • Even if DTC C1781 is stored at the same time, perform the inspection for DTC C1782 first.

  • Before performing troubleshooting, inspect the connectors of related circuits.

  • If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed Click here.

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (IG VOLTAGE)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and the tester on.

    3. Read the "IG Power Source Voltage" item in the Data List.

      AHC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      IG Power Source Voltage

      Power supply voltage /

      min.: 0 V

      max.: 255 V

      		 Engine switch on (IG): 11 to 14 V -
      OK
      11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (BATTERY - ECU AND BODY GROUND) Click here

    OK

  2. RECONFIRM DTC OUTPUT


    1. Clear the DTCs Click here.

    2. Check for DTCs.

      Result
      Result Proceed to
      DTC is output A
      DTC is not output B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

  3. READ VALUE USING INTELLIGENT TESTER (+B POWER SOURCE VOLTAGE, +B2 POWER SOURCE VOLTAGE)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG) and the tester on.

    3. Read the "+B Power Source Voltage" and "+B2 Power Source Voltage" items in the Data List.

      AHC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      +B Power Source Voltage

      Power supply for absorber control actuator /

      min.: 0 V

      max.: 255 V

      		 Engine switch on (IG): 11 to 14 V -
      +B2 Power Source Voltage

      Power supply for No. 1 height control valve and front suspension control valve /

      min.: 0 V

      max.: 255 V

      		 Engine switch on (IG): 11 to 14 V -
      OK
      11 to 14 V

    OK

    REPLACE SUSPENSION CONTROL ECU Click here

    NG

  4. INSPECT FUSE (AHC-B, AHC-B NO. 2)


    1. Remove the AHC-B and AHC-B No. 2 fuses from the cowl side junction block RH.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      AHC-B fuse Always Below 1 Ω
      AHC-B No. 2 fuse Always Below 1 Ω

    NG

    CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE

    OK

  5. CHECK HARNESS AND CONNECTOR (BATTERY - SUSPENSION CONTROL ECU)


    1. Disconnect the K34 and K35 ECU connectors.

    2. B001Z47E02
      *a Rear view of wire harness connector: (to Suspension Control ECU)

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      K34-3 (BAT2) - Body ground Engine switch on (IG) 11 to 14 V
      K35-1 (BAT) - Body ground Engine switch on (IG) 11 to 14 V

    OK

    REPLACE SUSPENSION CONTROL ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  6. CHECK HARNESS AND CONNECTOR (BATTERY - ECU AND BODY GROUND)


    1. B001YMLE02
      *a Rear view of wire harness connector: (to Suspension Control ECU)

      Disconnect the K34 ECU connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      K34-5 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Result
      Result Proceed to
      OK A
      NG (1UR-FE) B
      NG (1VD-FTV) C

    A

    REPLACE SUSPENSION CONTROL ECU Click here

    B

    BATTERY VOLTAGE IS LOW OR CHARGING SYSTEM HAS MALFUNCTION

    C

    BATTERY VOLTAGE IS LOW OR CHARGING SYSTEM HAS MALFUNCTION