Dtc C1241 Low Power Supply Voltage Malfunction

Brake. Corolla. Zre142 Aze141

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT ECU-IG NO. 1 FUSE

CHECK BATTERY

INSPECT SKID CONTROL ECU (IG1 TERMINAL)

INSPECT SKID CONTROL ECU (GND1 TERMINAL)

RECONFIRM DTC

DTC C1241 Low Power Supply Voltage Malfunction


DESCRIPTION

If a malfunction is detected in the power supply circuit, the skid control ECU (housed in the 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 alternator circuit, etc.
The DTC is cancelled when the IG1 terminal voltage returns to normal.

DTC Code
DTC Detection Condition
Trouble Area
C1241
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.
  1. ECU-IG NO. 1 fuse
  2. Battery
  3. Charging system
  4. Power source circuit
  5. Internal power supply circuit of the skid control ECU

WIRING DIAGRAM


Corolla. Zre142 Aze141.Brake Control Dynamic Control Systems.Anti-Lock Brake System.
Dtc
  C1241  Low Power Supply Voltage Malfunction


INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (COROLLA_ZRE142 RM000000XHR08KX.html).
1.INSPECT ECU-IG NO. 1 FUSE


    Corolla. Zre142 Aze141.Brake Control Dynamic Control Systems.Anti-Lock Brake System.
Dtc
  C1241  Low Power Supply Voltage Malfunction
  1. Remove the ECU-IG NO. 1 fuse from the main body ECU (instrument panel junction block).

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    ECU-IG NO. 1 (10 A) fuse
    Always
    Below 1 Ω


NG
REPLACE ECU-IG NO. 1 FUSE
OK


2.CHECK BATTERY
  1. Install the ECU-IG NO. 1 fuse.

  1. Check the battery voltage.

    Standard Voltage:
    11 to 14 V

    Result:

    Result
    Proceed to
    OK
    A
    NG (for 2AZ-FE)
    B
    NG (for 2ZR-FE)
    C


B
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (for 2AZ-FE) (COROLLA_ZRE142 RM000001AR909TX.html)

C
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (for 2ZR-FE) (COROLLA_ZRE142 RM000001AR909SX.html)
A


3.INSPECT SKID CONTROL ECU (IG1 TERMINAL)


    Corolla. Zre142 Aze141.Brake Control Dynamic Control Systems.Anti-Lock Brake System.
Dtc
  C1241  Low Power Supply Voltage Malfunction
  1. Make sure that there is no looseness at the locking part and the connecting part of the connector.

  1. Disconnect the skid control ECU connector.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    Switch Condition
    Specified Condition
    A66-34 (IG1) - Body ground
    Ignition switch ON
    11 to 14 V


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK


4.INSPECT SKID CONTROL ECU (GND1 TERMINAL)


    Corolla. Zre142 Aze141.Brake Control Dynamic Control Systems.Anti-Lock Brake System.
Dtc
  C1241  Low Power Supply Voltage Malfunction
  1. Turn the ignition switch off.

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

    Standard Resistance:
    Tester Connection
    Condition
    Specified Condition
    A66-1 (GND1) - Body ground
    Always
    Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)
OK


5.RECONFIRM DTC
  1. Reconnect the skid control ECU connector.

  1. Clear the DTCs (COROLLA_ZRE142 RM000000XHV0F2X.html).

  1. Start the engine.

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

  1. Check if the same DTC is recorded (COROLLA_ZRE142 RM000000XHV0F2X.html).

    Result:

    Result
    Proceed to
    DTC (C1241) is not output
    A
    DTC (C1241) is output
    B
    HINT:
    If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step (COROLLA_ZRE142 RM000000XHN0DUX.html).


B
REPLACE BRAKE ACTUATOR ASSEMBLY (COROLLA_ZRE142 RM000003CZU00MX.html)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (COROLLA_ZRE142 RM000000XHP0EKX.html)