VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1241

DTC Code DTC Name
C1241 Low Power Supply Voltage Malfunction

DESCRIPTION

If a malfunction is detected in the power supply circuit, the skid control ECU (brake actuator assembly) stores this DTC and the fail-safe function prohibits ABS operation.

This DTC is stored when the IG1 terminal voltage deviates from the DTC detection condition due to a malfunction in the power supply or charging circuit such as the battery or generator circuit, etc.

The DTC is canceled when the IG1 terminal voltage returns to normal.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1241

Low Power Supply Voltage Malfunction

When any of the following is detected:

  1. At a vehicle speed of 3 km/h (2 mph) or more, the IG1 terminal voltage is less than 9.5 V for 10 seconds or more.

  2. When the solenoid relay remains ON and the IG1 terminal voltage is less than 9.5 V, the relay contact is open for 0.22 seconds or more.

  3. With the IG1 terminal voltage 9.5 V or less, the vehicle speed sensor power supply decreases for 60 seconds or more.

  4. When the motor fail safe relay is ON after the motor relay turns ON, the IG1 terminal voltage is 9.5 V or less and the actuator pump drive motor is OFF for 0.22 seconds or more.

  • ECU-IG NO. 3 fuse

  • Battery

  • Charging system

  • Backup boost converter circuit (w/ Stop and Start System)

  • Power source circuit

  • Internal power supply circuit of the skid control ECU (Brake actuator assembly)

WIRING DIAGRAM

C279050E01

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 inspection procedure.

PROCEDURE

  1. INSPECT BATTERY

    1. Check the battery voltage.

      Standard voltage

      11 to 14 V

      Result

      Proceed to

      OK

      NG (for 1AD-FTV)

      NG (for 2AD-FHV)

      NG (for 2AD-FTV)

      NG (for 2AR-FE)

      NG (for 3ZR-FAE)

      NG (for 3ZR-FE)
    NG (for 1AD-FTV)

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    Click here

    NG (for 2AD-FHV)

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    Click here

    NG (for 2AD-FTV)

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    Click here

    NG (for 2AR-FE)

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    Click here

    NG (for 3ZR-FAE)

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    Click hereClick here

    NG (for 3ZR-FE)

    CHECK OR REPLACE CHARGING SYSTEM OR BATTERY

    Click here

    OK

  2. CHECK TERMINAL VOLTAGE (IG1 TERMINAL)

    1. Make sure that there is no looseness in the locking part and connecting part of the connectors.

    2. C199357C49

      *a

      Front view of wire harness connector

      (to Skid Control ECU [Brake Actuator Assembly])

      Disconnect the A64 skid control ECU (brake actuator assembly) connector.

    3. Turn the ignition switch to ON.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      A64-34 (IG1) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG (w/o Stop and Start System)

    NG (w/ Stop and Start System)
    NG (w/o Stop and Start System)

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)

    NG (w/ Stop and Start System)

    INSPECT STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT)

    OK

  3. CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

    1. Turn the ignition switch off.

    2. C199357C53

      *a

      Front view of wire harness connector

      (to Skid Control ECU [Brake Actuator Assembly])

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      A64-1 (GND1) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

    OK

  4. RECONFIRM DTC

    1. Reconnect the A64 skid control ECU (brake actuator assembly) connector.

    2. Clear the DTC.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    3. Start the engine.

    4. Drive the vehicle at a speed of 20 km/h (12 mph) or more for 30 seconds or more.

    5. Check if the same DTC is recorded.

      Click here

      Chassis > ABS/VSC/TRC > Trouble Codes

      Tip:

      If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step.

      Click here

    Result

    Proceed to

    DTC C1241 is not output

    DTC C1241 is output
    DTC C1241 is not output

    USE SIMULATION METHOD TO CHECK

    Click hereClick hereClick hereClick here

    DTC C1241 is output

    REPLACE BRAKE ACTUATOR ASSEMBLY

    Click here