DTC    C1241/41    Low Battery Positive Voltage

DTC    C1242/42    Open in IG1 / IG2 Power Source Circuit

for Preparation Click here


DESCRIPTION

These codes are memorized when the power source voltage for the skid control ECU drops or the voltage for the ABS No.1, ABS No.2 relay operation drops.
Codes may be memorized when the voltage of the auxiliary battery temporarily drops.
When the power source voltage is too high, the skid control ECU stops functioning and outputs no DTCs, and the ABS and BRAKE warning lights remain on.

HINT:
DTC C1256/56 (accumulator low voltage malfunction) may be memorized if the power source voltage drops.


DTC No.
INF Code
DTC Detecting Condition
Trouble Area
C1241/41
81
System 1 is under the following conditions when the vehicle is in the READY-on state:
  1. Linear solenoid cannot receive enough current (brake is applied).
  2. BS voltage is less than 8.9 V for at least 3 sec. (brake is not applied).
  3. 12 V-power source voltage inside ECU is less than 8.5 V when main relay is opened or VCM voltage is less than 4.7 V or 5 V or more for at least 0.05 sec.
  1. Battery
  2. Charging system
  3. ABS No.1 relay
  4. Wire harness or connector
  5. Brake control power supply assembly
  6. HV control system
  7. Skid control ECU
C1241/41
82
System 2 is under the following conditions when the vehicle is in the READY-on state:
  1. Linear solenoid cannot receive enough current (brake is applied).
  2. BS voltage is less than 8.9 V for at least 3 sec. (brake is not applied).
  3. 12 V-power source voltage inside ECU is less than 8.5 V when main relay is opened or VCM voltage is less than 4.7 V or 5.3 V or more for at least 0.05 sec.
  1. Battery
  2. Charging system
  3. ABS No.2 relay
  4. Wire harness or connector
  5. Brake control power supply assembly
  6. HV control system
  7. Skid control ECU
C1241/41
83
Capacitor mode signal is received from brake control power supply for 3 sec. or more when the vehicle is in the READY-on state.
  1. Battery
  2. Charging system
  3. Wire harness or connector
  4. Brake control power supply assembly
  5. HV control system
  6. Skid control ECU
C1241/41
84
ABS is requested to operate when the power source voltage of the main relay system is dropping.
  1. ABS No.1 relay
  2. ABS No.2 relay
  3. Wire harness or connector
  4. Brake control power supply assembly
  5. HV control system
  6. Skid control ECU
C1242/42
87
Voltage is applied to IG2 terminal, but not applied to IG1 terminal for at least 4 sec.
  1. Battery
  2. Charging system
  3. ABS No.1 relay
  4. Wire harness or connector
  5. Brake control power supply assembly
  6. HV control system
  7. Skid control ECU
C1242/42
88
Voltage is applied to IG1 terminal, but not applied to IG2 terminal for at least 4 sec.
  1. Battery
  2. Charging system
  3. ABS No.2 relay
  4. Wire harness or connector
  5. Brake control power supply assembly
  6. HV control system
  7. Skid control ECU

WIRING DIAGRAM


C112016E02


C112017E03


C112018E03


INSPECTION PROCEDURE

NOTICE:
When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (Click here).

1.CHECK DTC (HYBRID CONTROL SYSTEM)
  1. Check if DTC for the HYBRID CONTROL SYSTEM is output (Click here).

    Result:

    Condition
    Proceed To
    DTC is not output
    A
    DTC is output
    B



B
REPAIR HYBRID CONTROL SYSTEM
A


2.CHECK AUXILIARY BATTERY VOLTAGE
  1. Check the auxiliary battery voltage.

    Voltage:
    10 to 14 V



NG
CHARGE OR PEPLACE AUXILIARY BATTERY
OK


3.CHECK BRAKE CONTROL POWER SUPPLY


    F100411E04
  1. Measure the voltage according to the value(s) in the table below.

    HINT:
    Measure the voltage from the back side of the connector with the connector connected.

    Voltage:
    Tester Connection
    Specified Condition
    B22-5 (IG1)- Body ground
    10 to 14 V



NG
REPLACE BRAKE CONTROL POWER SUPPLY
OK


4.CHECK HARNESS AND CONNECTOR


    F047485E18
  1. Measure the voltage according to the value(s) in the table below.

    HINT:
    Measure the voltage from the back side of the connector with the connector connected to the skid control ECU.

    Voltage:
    Tester Connection
    Specified Condition
    S40-7 (IG1) - Body ground
    10 to 14 V
    S38-5 (IG2) - Body ground
    10 to 14 V
    S40-3 (+BI1) - Body ground
    10 to 14 V
    S39-5 (+BI2) - Body ground
    10 to 14 V

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

    Resistance:
    Tester Connection
    Specified Condition
    S41-1 (GND1) - Body ground
    Below 1 Ω
    S40-2 (GND2) - Body ground
    Below 1 Ω
    S40-1 (GND3) - Body ground
    Below 1 Ω
    S39-2 (GND4) - Body ground
    Below 1 Ω
    S39-1 (GND5) - Body ground
    Below 1 Ω
    S38-4 (GND6) - Body ground
    Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.INSPECT SKID CONTROL ECU


    F047485E19
  1. Measure the voltage according to the value(s) in the table below.

    HINT:
    Measure the voltage from the back side of the connector with the connector connected to the skid control ECU.

    Voltage:
    Tester Connection
    Condition
    Specified Condition
    S41-2 (R1+) - Body ground
    Ignition switch ON
    8 to 13 V
    S38-17 (R2+) - Body ground
    Ignition switch ON
    8 to 13 V
    S41-12 (R3+) - Body ground
    Ignition switch ON
    Below 1.5 V
    S38-15 (R4+) - Body ground
    Ignition switch ON
    Below 1.5 V
    S41-3 (BS1) - Body ground
    Ignition switch ON
    10 to 14 V
    S38-7 (BS2) - Body ground
    Ignition switch ON
    10 to 14 V


    Result:

    Condition
    Proceed To
    All OK
    A
    NG (R1+, R2+)
    B
    NG (SR1, SR2, BS1, BS2)
    C



B
REPLACE SKID CONTROL ECU

C
REPAIR OR REPLACE HARNESS OR CONNECTOR
A


6.RECONFIRM DTC
  1. Clear the DTCs (Click here).

  1. Turn the ignition switch on.

  1. Check the same DTCs are recorded (Click here).

    Result:

    Condition
    Proceed To
    DTC is not output
    A
    DTC is output
    B



B
REPLACE SKID CONTROL ECU
A

END