Dtc C1241/41 Low Battery Positive Voltage

Brake. Lexus Is250, Is220D. Gse20 Ale20
Brake Control. Lexus Is250, Is220D. Gse20 Ale20

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT ECU-IG RH FUSE

CHECK BATTERY

INSPECT SKID CONTROL ECU (IG1 TERMINAL)

INSPECT SKID CONTROL ECU (GND TERMINAL)

RECONFIRM DTC

DTC C1241/41 Low Battery Positive Voltage


DESCRIPTION

If a malfunction is detected in the power supply circuit, the skid control ECU (housed in the actuator assembly) outputs the DTC and prohibits operation with the fail safe function.
This DTC is stored when the IG1 terminal voltage deviates from the DTC detecting 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 No.
DTC Detection Condition
Trouble Area
C1241/41
When any of the following is detected:
  1. At a vehicle speed of 2 mph (3 km/h) or more, the IG1 terminal voltage is 9.5 V or less for 10 seconds or more.
  2. When the solenoid relay remains ON and the IG1 terminal voltage is 9.5 V or less, the relay contact is open for 0.2 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. Battery
  2. Charging system
  3. Power source circuit
  4. Internal power supply circuit of the skid control ECU

WIRING DIAGRAM


Lexus Is250, Is220D. Gse20 Ale20.Brake Control.Vehicle Stability Control System (W/ Vdim). Dtc C1241/41 Low Battery Positive Voltage


INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (Click here).
1.INSPECT ECU-IG RH FUSE


    Lexus Is250, Is220D. Gse20 Ale20.Brake Control.Vehicle Stability Control System (W/ Vdim). Dtc C1241/41 Low Battery Positive Voltage

  1. Remove the ECU-IG RH fuse from the main body ECU RH.

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    ECU-IG RH (10A) fuse
    		Always
    		Below 1 Ω


NG
REPLACE ECU-IG RH FUSE
OK


2.CHECK BATTERY

  1. Install the ECU-IG RH fuse.

  1. Check the battery voltage.

    Standard voltage:
    10 to 14 V


NG
CHECK AND REPLACE CHARGING SYSTEM OR BATTERY
OK


3.INSPECT SKID CONTROL ECU (IG1 TERMINAL)


    Lexus Is250, Is220D. Gse20 Ale20.Brake Control.Vehicle Stability Control System (W/ Vdim). Dtc C1241/41 Low Battery Positive Voltage

  1. Disconnect the skid control ECU connector.

  1. Turn the engine switch on (IG).

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

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A14-46 (IG1) - Body ground
    		Engine switch on (IG)
    		10 to 14 V


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


4.INSPECT SKID CONTROL ECU (GND TERMINAL)


    Lexus Is250, Is220D. Gse20 Ale20.Brake Control.Vehicle Stability Control System (W/ Vdim). Dtc C1241/41 Low Battery Positive Voltage

  1. Turn the engine switch off.

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A14-32 (GND1) - Body ground
    		Always
    		Below 1 Ω
    A14-1 (GND2) - Body ground
    		Always
    		Below 1 Ω


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


5.RECONFIRM DTC

  1. Reconnect the skid control ECU connector.

  1. Clear the DTC (Click here).

  1. Turn the engine switch on (IG).

  1. Check if the same DTC is recorded (Click here).

    Result:

    Condition
    		Proceed to
    DTC (C1241/41) is not output
    		A
    DTC (C1241/41) 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 (Click here).


B
REPLACE BRAKE ACTUATOR ASSEMBLY
A

USE SIMULATION METHOD TO CHECK