DTC    C1241    Low Power Supply Voltage Malfunction

for Preparation Click here


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 Code
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 vehicle speed sensor power supply decreases for 60 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


C212076E02


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the brake actuator assembly, perform zero point calibration (Click here).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.

1.INSPECT BATTERY

  1. Check the battery voltage.

    Standard voltage:
    11 to 14 V



NG
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (Click here)
OK


2.INSPECT SKID CONTROL ECU (IG1 TERMINAL)

  1. Disconnect the A16 or A17 skid control ECU connector.

  1. Turn the ignition switch to ON.



    E175972E15

  1. Measure the voltage according to the value(s) in the table below.
    Text in Illustration 
    *A
    		for LHD
    *B
    		for RHD
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

    Standard Voltage:
    for LHD 
    Tester Connection
    		Switch Condition
    		Specified Condition
    A16-34 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V
    for RHD 
    Tester Connection
    		Switch Condition
    		Specified Condition
    A17-34 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V

    Result 
    Result
    		Proceed to
    OK
    		A
    NG (w/ Stop and Start System)
    		B
    NG (w/o Stop and Start System)
    		C



B
GO TO STOP AND START SYSTEM (Click here)

C
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
A


3.INSPECT SKID CONTROL ECU (GND TERMINAL)

  1. Turn the ignition switch off.



    E175972E14

  1. Measure the resistance according to the value(s) in the table below.
    Text in Illustration 
    *A
    		for LHD
    *B
    		for RHD
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

    Standard Resistance:
    for LHD 
    Tester Connection
    		Condition
    		Specified Condition
    A16-1 (GND1) - Body ground
    		Always
    		Below 1 Ω
    for RHD 
    Tester Connection
    		Condition
    		Specified Condition
    A17-1 (GND1) - Body ground
    		Always
    		Below 1 Ω



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


4.RECONFIRM DTC

  1. Reconnect the skid control ECU connector.

  1. Clear the DTC (Click here).

  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 (Click here).
    Result 
    Result
    		Proceed to
    DTC not output
    		A
    DTC 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 (Click here).



B
REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)
A

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (Click here)