Dtc C1241 Low Power Supply Voltage Malfunction

Brake. Yaris. Ncp93, 131
Brake Control Dynamic Control Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT BATTERY

CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)

CHECK HARNESS AND CONNECTOR (GND1, GND2 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 generator circuit, etc.
The DTC is cancelled when the IG1 terminal voltage returns to normal.

DTC NO.
DTC Detection Condition
Trouble Area
C1241
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 speed sensor power supply voltage decreases for 60 seconds or more.
  4. While the motor relay remains ON and the IG1 terminal voltage is less than 9.5 V, the relay contact is closed for 0.22 seconds or more.
  1. Battery
  2. Charging system
  3. Harness or connector
  4. Brake actuator assembly (skid control ECU)

WIRING DIAGRAM


Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan). Dtc C1241 Low Power Supply Voltage Malfunction


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.INSPECT BATTERY

  1. Inspect the battery voltage.

    Standard Voltage:
    11 to 14 V


NG
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (YARIS_NCP93 RM000001E2J01FX.html)
OK


2.CHECK HARNESS AND CONNECTOR (IG1 TERMINAL)

  1. Turn the ignition switch off.

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

  1. Disconnect the A15 brake actuator assembly (skid control ECU) connector.

  1. Check the connector case and terminals for deformation and corrosion.

    OK:
    No deformation or corrosion.


    Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan). Dtc C1241 Low Power Supply Voltage Malfunction

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A15-34 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Brake Actuator Assembly (Skid Control ECU))


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


3.CHECK HARNESS AND CONNECTOR (GND1, GND2 TERMINAL)

  1. Turn the ignition switch off.



    Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan). Dtc C1241 Low Power Supply Voltage Malfunction

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A15-1 (GND1) - Body ground
    		Always
    		Below 1 Ω
    A15-13 (GND2) - Body ground
    		Always
    		Below 1 Ω
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Brake Actuator Assembly (Skid Control ECU))

  1. Reconnect the A15 brake actuator assembly (skid control ECU) connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1, GND2 CIRCUIT)
OK


4.RECONFIRM DTC

  1. Clear the DTC (YARIS_NCP93 RM000000XHV0BPX.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 (YARIS_NCP93 RM000000XHV0BPX.html).

    Result
    Result
    		Proceed to
    DTC is not output
    		A
    DTC is output
    		B
HINT:
If troubleshooting has been carried out according to the Problem Symptoms Table, refer back to the table and proceed to the next step (YARIS_NCP93 RM000000XHN0AWX.html).


B
REPLACE BRAKE ACTUATOR ASSEMBLY (YARIS_NCP93 RM000001BXP02FX.html)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (YARIS_NCP93 RM000000UZ309WX.html)