Dtc C1241 Low Power Supply Voltage Malfunction


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (IG1 VOLTAGE VALUE)

RECONFIRM DTC

CHECK TERMINAL VOLTAGE (IG1)

CHECK HARNESS AND CONNECTOR (GND1, GND2, AND GND3 TERMINAL)

RECONFIRM DTC

DTC C1241 Low Power Supply Voltage Malfunction


DESCRIPTION

If the voltage supplied to the IG1 terminal is within the DTC detection range due to malfunctions in components such as the battery and generator circuit, this DTC is stored.

DTC Code
DTC Detection Condition
Trouble Area
C1241
Either condition is met:
1. Both of the following conditions continue for at least 10 seconds.
  1. The vehicle speed is more than 3 km/h (2 mph).
  2. The IG1 terminal voltage is below 9.5 V.
2. All of the following conditions continue for at least 0.2 seconds.
  1. The solenoid relay remains on.
  2. The IG1 terminal voltage is below 9.5 V.
  3. The relay contact is open.
  1. Battery
  2. ECU-IG NO. 1 fuse
  3. Charging system
  4. Harness or connector
  5. Master cylinder solenoid (Skid control ECU)

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System. Dtc C1241 Low Power Supply Voltage Malfunction


INSPECTION PROCEDURE

NOTICE:
  1. When replacing the master cylinder solenoid, perform calibration (LandCruiser RM00000452J00ZX.html).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.READ VALUE USING INTELLIGENT TESTER (IG1 VOLTAGE VALUE)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Start the engine.

  1. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

    ABS/VSC/TRC
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    IG1 Voltage Value
    		IG1 voltage value/ Min.: 0.00 V, Max.: 20.00 V
    		Ignition switch ON: 11 to 14 V
    		-

  1. Check the voltage output from the skid control ECU displayed on the intelligent tester.

    OK:
    The output voltage displayed on the intelligent tester is within 11 to 14 V.


NG
Go to step 3
OK


2.RECONFIRM DTC

  1. Clear the DTCs (LandCruiser RM0000046KV016X.html).

  1. Check if the same DTCs are output (LandCruiser RM0000046KV016X.html).

    HINT:
    Reinstall the sensors, connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

    Result
    Result
    		Proceed to
    DTC is output (for LHD)
    		A
    DTC is output (for RHD)
    		B
    DTC is not output (When troubleshooting in accordance with Diagnostic Trouble Code Chart)
    		C
    DTC is not output (When troubleshooting in accordance with Problem Symptoms Table)
    		D


B
REPLACE MASTER CYLINDER SOLENOID (LandCruiser RM00000171U02EX.html)

C
USE SIMULATION METHOD TO CHECK (LandCruiser RM000003YMJ00XX.html)

D
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM000000OS705AX.html)
A

REPLACE MASTER CYLINDER SOLENOID (LandCruiser RM00000171U02DX.html)

3.CHECK TERMINAL VOLTAGE (IG1)

  1. Disconnect the A7 skid control ECU connector.



    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System. 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
    A7-46 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Skid Control ECU)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


4.CHECK HARNESS AND CONNECTOR (GND1, GND2, AND GND3 TERMINAL)

  1. Disconnect the A7 and A8 skid control ECU connectors.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A7-1 (GND1) - Body ground
    		Always
    		Below 1 Ω
    A7-32 (GND2) - Body ground
    		Always
    		Below 1 Ω
    A8-4 (GND3) - Body ground
    		Always
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.RECONFIRM DTC

  1. Clear the DTCs (LandCruiser RM0000046KV016X.html).

  1. Check if the same DTCs are output (LandCruiser RM0000046KV016X.html).

    HINT:
    Reinstall the sensors, connectors, etc. and restore the previous vehicle conditions before rechecking for DTCs.

    Result
    Result
    		Proceed to
    DTC is output (for LHD)
    		A
    DTC is output (for RHD)
    		B
    DTC is not output (When troubleshooting in accordance with Diagnostic Trouble Code Chart)
    		C
    DTC is not output (When troubleshooting in accordance with Problem Symptoms Table)
    		D


B
REPLACE MASTER CYLINDER SOLENOID (LandCruiser RM00000171U02EX.html)

C
USE SIMULATION METHOD TO CHECK (LandCruiser RM000003YMJ00XX.html)

D
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM000000OS705AX.html)
A

REPLACE MASTER CYLINDER SOLENOID (LandCruiser RM00000171U02DX.html)