ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C1241/41

DTC Code DTC Name
C1241/41 Low Battery Positive Voltage or Abnormally High Battery Positive Voltage

DESCRIPTION

When there is an abnormality in the power supply circuit of the brake actuator (skid control ECU), the skid control ECU sets a DTC and the operation is prohibited by the fail-safe function. This DTC is set when the voltage supplied to terminal IG1 is outside DTC detection thresholds, due to abnormalities of the battery, power source circuits or charging circuits such as the alternator circuit.

Fail-safe function is canceled when the voltage to terminal IG1 returns to normal.

DTC No. DTC Detecting Conditions Trouble Areas
C1241/41

When either of following (1 or 2) detected:

1. At vehicle speed of 6 km/h (4 mph) or more, terminal IG1 voltage 9.6 V or less when no ABS control, or 9.3 V or less during ABS control.

2. Terminal IG voltage 16.9 V or more.

  • Battery

  • Charging system

  • Power source circuit

WIRING DIAGRAM

A0136ACE01
A0137MFE01

INSPECTION PROCEDURE

PROCEDURE


  1. INSPECT SKID CONTROL ECU TERMINAL VOLTAGE


    1. When using an intelligent tester:


      1. Connect the intelligent tester to the DLC3.

      2. Start the engine.

      3. Turn the tester ON.

      4. Read the value using the intelligent tester.

        Select the following menu items: Chassis / ABS/VSC/TRC / Data List.

        Item Measurement Item : Range (Display) Normal Condition
        ECU IG Power Voltage ECU power supply voltage : TOO LOW / NORMAL / TOO HIGH

        TOO HIGH: 14.0 V or more

        NORMAL: 9.5 to 14.0 V

        TOO LOW: Below 9.5 V
        OK
        "Normal" is displayed.

    2. When not using an intelligent tester:


      1. Disconnect the skid control ECU connector.

      2. Turn the ignition switch to the ON position.

      3. Measure the voltage.

        Standard Voltage
        Tester Connection Specified Condition
        A21-18 (IG1) - Body ground 10 to 14 V

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  2. INSPECT FUSE (ECU-IG)


    1. A01391UE01

      Remove the ECU-IG fuse from the instrument panel J/B.

    2. Measure the resistance.

      Standard Resistance
      Below 1 Ω

    NG

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

    OK

  3. INSPECT BATTERY


    1. Check the battery voltage.

      Standard Voltage
      11 to 14 V

    NG

    CHECK CHARGING SYSTEM

    OK

  4. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BODY GROUND)


    1. Inspect the skid control ECU connector fitting for any defects.

    2. Disconnect the skid control ECU connector.

    3. Inspect both the connector case and the terminal for deformation and corrosion.

      OK
      No deformation or corrosion.
    4. A0135VYE05

      Measure the resistance.

      Standard Resistance
      Tester Connection Specified Condition
      A21-4 (GND1) - Body ground Below 1 Ω
      A21-1 (GND2) - Body ground Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS AND CONNECTOR

    OK

  5. RECONFIRM DTC


    1. Clear the DTC Click here.

    2. Drive the vehicle at 6 km/h (4 mph) or more for several seconds.

    3. Check if the same DTC is output.

      Result
      DTC output A
      DTC not output B

    B

    END

    A

    REPLACE BRAKE ACTUATOR