Code C1241 Low Battery Positive Voltage Toyota

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT BATTERY

INSPECT ECU-IG NO. 2 FUSE

READ VALUE USING INTELLIGENT TESTER (IG1 VOLTAGE VALUE)

RECONFIRM DTC

INSPECT SKID CONTROL ECU (IG1 TERMINAL)

INSPECT SKID CONTROL ECU (GND TERMINAL)

RECONFIRM DTC

DTC C1241/41 Low Battery Positive Voltage

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 alternator circuit, this DTC is stored.

DTC Code DTC Detection Condition Trouble Area
C1241/41 When either of the following conditions is detected: 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. 2 fuse
  3. Charging system
  4. Harness or connector
  5. Master cylinder solenoid (Skid control ECU)

Wiring diagram

Diagnostic trouble code C1241 Land Cruiser. Wiring diagram

Inspection procedure

NOTICE:

When replacing the master cylinder solenoid, perform zero point calibration .

1.INSPECT BATTERY

  1. Check the battery voltage.

    Standard voltage:

    11 to 14 V

    Result
    Result Proceed to
    OK A
    NG 1GR-FE B
    2UZ-FE C
    1VD-FTV D
  B  
GO TO CHARGING SYSTEM (ON-VEHICLE INSPECTION)
 
  C  
GO TO CHARGING SYSTEM (ON-VEHICLE INSPECTION)
 
  D  
GO TO CHARGING SYSTEM (ON-VEHICLE INSPECTION)
 
A  
   

2.INSPECT ECU-IG NO. 2 FUSE

Diagnostic trouble code C1241 Land Cruiser. Remove the ECU-IG No. 2 fuse from the main body ECU (cowl side junction block LH).

  1. Remove the ECU-IG No. 2 fuse from the main body ECU (cowl side junction block LH).

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

    Standard Resistance:

    Tester Connection Condition Specified Condition
    ECU-IG No. 2 fuse Always Below 1 ?
  NG  
REPLACE ECU-IG NO. 2 FUSE
 
OK  
   

3.READ VALUE USING INTELLIGENT TESTER (IG1 VOLTAGE VALUE)

  1. Install the ECU-IG No. 2 fuse.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and 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 V, max.: 255 V 9.5 to 14.0 V -

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

    OK:

    The output voltage displayed on the intelligent tester is within 9.5 to 14.0 V.

  NG  
Go to step 5
 
OK  
   

4.RECONFIRM DTC

  1. Clear the DTCs .

  1. Check if the same DTCs are output .

    HINT:

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

    Result
    Result Proceed to
    DTC is output LHD A
    RHD B
    DTC is not output (When troubleshooting in accordance with the Diagnostic Trouble Code Chart) C
    DTC is not output (When troubleshooting in accordance with the Problem Symptoms Table) D
  B  
REPLACE MASTER CYLINDER SOLENOID
 
  C  
USE SIMULATION METHOD TO CHECK
 
  D  
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
 
A  
   
REPLACE MASTER CYLINDER SOLENOID

5.INSPECT SKID CONTROL ECU (IG1 TERMINAL)

Diagnostic trouble code C1241 Land Cruiser. Disconnect the A24 skid control ECU connector.

  1. Disconnect the A24 skid control ECU connector.

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

    Standard Voltage:

    Tester Connection Switch Condition Specified Condition
    A24-46 (IG1) - Body ground Ignition switch ON 11 to 14 V
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

6.INSPECT SKID CONTROL ECU (GND TERMINAL)

Diagnostic trouble code C1241 Land Cruiser. Disconnect the A24 and A25 skid control ECU connectors.

  1. Disconnect the A24 and A25 skid control ECU connectors.

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

    Standard Resistance:

    Tester Connection Condition Specified Condition
    A24-1 (GND1) - Body ground Always Below 1 ?
    A24-32 (GND2) - Body ground Always Below 1 ?
    A25-4 (GND3) - Body ground Always Below 1 ?
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

7.RECONFIRM DTC

  1. Clear the DTCs .

  1. Check if the same DTCs are output .

    HINT:

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

    Result
    Result Proceed to
    DTC is output LHD A
    RHD B
    DTC is not output (When troubleshooting in accordance with the Diagnostic Trouble Code Chart) C
    DTC is not output (When troubleshooting in accordance with the Problem Symptoms Table) D
  B  
REPLACE MASTER CYLINDER SOLENOID
 
  C  
USE SIMULATION METHOD TO CHECK
 
  D  
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
 
A  
   
REPLACE MASTER CYLINDER SOLENOID