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ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1241, C1242

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DTC Code DTC Name
C1241 Low or High Power Supply Voltage
C1242 Open Circuit in IG1/IG2 Power Source Circuit
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DESCRIPTION

If a malfunction is detected in the power supply circuit, the skid control ECU assembly power source voltage drops, or there is insufficient voltage to operate the ABS main relay, the skid control ECU assembly will store these DTCs.

These DTCs may also be stored if the auxiliary battery voltage drops below 9.5 V.

Tip:

DTC C1256 (Accumulator Low Pressure) may also be memorized if there is a drop in power source voltage.

DTC No. Detection Item INF Code DTC Detection Condition Trouble Area Note
C1241 Low or High Power Supply Voltage

81

82

83

91

92

93

94

  • INF Code: 81


    • System ABS main relay 1 is under the following conditions when the power switch is on (READY):


      1. With the ABS main relay 1 and the relay contact on, the voltage of relay power supply terminal (BS01) is less than 8.9 V and the actual current, which is supplied by the relay, does not reach the specified value at any of the linear solenoids for 0.03 seconds or more.

      2. With the ABS main relay 1 and the relay contact on, the voltage of relay power supply terminal (BS01) is less than 8.9 V and the brake pedal is not depressed for 3 seconds or more.

      3. When 0.05 seconds have elapsed after ABS main relay 1 is turned on and the relay contact is on, the voltage of relay power supply terminal (BS01) is less than 8.9 V and even one wheel is prohibited from braking while depressing the brake pedal.

      4. While the ABS main relay 1 on continues, skid control ECU assembly activation power source input terminal (+BI1 or +BI3) becomes lower than 9.1 V and the relay contact off continues for 0.2 seconds or more.

      5. With the pressure sensor power supply voltage (VCM) 4.7 V or less or 5.3 V or more, skid control ECU assembly activation power source input terminal (+BI1 or +BI3) in the relevant lines is 9.1 V or less for 0.05 seconds or more.

      6. The brake pedal stroke sensor output voltage 1 (SKS) or brake pedal stroke sensor output voltage 2 (SKS2) terminal voltage remains below 0.26 V or 4.89 V or more, or the brake pedal stroke sensor power source voltage (VCSK) remains 4.67 V or less or 5.41 V or more for 0.2 seconds or more

  • INF Code: 82


    • System ABS main relay 2 is under the following conditions when the power switch is on (READY):


      1. With the ABS main relay 2 and the relay contact on, the voltage of relay power supply terminal (BS02) is less than 8.9 V and the actual current, which is supplied by the relay, does not reach the specified value at any of the linear solenoids for 0.03 seconds or more.

      2. With the ABS main relay 2 and the relay contact on, the voltage of relay power supply terminal (BS02) is less than 8.9 V and the brake pedal is not depressed for 3 seconds or more.

      3. When 0.05 seconds have elapsed after ABS main relay 2 is turned on and the relay contact is on, the voltage of relay power supply terminal (BS02) is less than 8.9 V and even one wheel is prohibited from braking while depressing the brake pedal.

      4. While the ABS main relay 2 on continues, skid control ECU assembly activation power source input terminal (+BI2 or +BI4) becomes lower than 9.1 V and the relay contact off continues for 0.2 seconds or more.

      5. With the pressure sensor power supply voltage (VCM2) 4.7 V or less or 5.3 V or more, skid control ECU assembly activation power source input terminal (+BI2 or +BI4) in the relevant lines is 9.1 V or less for 0.05 seconds or more.

      6. The brake pedal stroke sensor output voltage 1 (SKS) or brake pedal stroke sensor output voltage 2 (SKS2) terminal voltage remains below 0.26 V or 4.89 V or more, or the brake pedal stroke sensor power source voltage (VCSK) remains 4.67 V or less or 5.41 V or more for 0.2 seconds or more

  • INF Code: 83


    • With the power switch on (READY), the capacitor mode signal is received from the brake control power supply with bracket assembly while the vehicle is driven at low speed for 7 seconds or more, or the vehicle is driven at medium to high speed for 3 seconds or more.

  • INF Code: 91, 92


    • Either of the following is detected:


      1. The voltage of terminal IG1 or IG2 is 3.5 V or more, and when the vehicle speed is 3 km/h (2 mph) or more, the voltage of terminal IG1 is 9.5 V or less for 10 seconds or more.

      2. The voltage of terminal IG1 or IG2 is 3.5 V or more, and when the vehicle speed is 3 km/h (2 mph) or more, the voltage of terminal (+BI1 and +BI3 or +BI2 and +BI4) is 9.1 V or less for 10 seconds or more.

  • INF Code: 93, 94


    • Either of the following is detected:


      1. The voltage of terminal IG1 is 3.5 V or more, and with the voltage of terminal +BI1 and +BI3 at 9.1 V or less, the front wheel speed sensor RH and rear wheel speed sensor LH power supply voltage decreases for 60 seconds or more.

      2. The voltage of terminal IG2 is 3.5 V or more, and with the voltage of terminal +BI2 and +BI4 at 9.1 V or less, the front wheel speed sensor LH and rear wheel speed sensor RH power supply voltage decreases for 60 seconds or more.

  • INF Code: 81, 82, 91, 92


    • Improperly connected connector, deformation or corrosion of terminals

    • Auxiliary battery

    • Hybrid control system (Charging circuit)

  • INF Code: 83


    • Auxiliary battery

    • Hybrid control system (Charging circuit)

    • Brake control power supply with bracket assembly

  • INF Code: 93, 94


    • Open or short in IG1 circuit

    • Improperly connected connector, deformation or corrosion of terminals

    • Auxiliary battery

    • Hybrid control system (Charging circuit)

    • Skid control ECU assembly

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C1242 Open Circuit in IG1/IG2 Power Source Circuit

87

88

  • INF Code: 87


    • The power supply voltage is not applied to the IG1 terminal, power supply voltage is applied to the IG2 terminal, and +BI1 terminal voltage is 9.5 V or more for 4 seconds or more.

  • INF Code: 88


    • The power supply voltage is applied to the IG1 terminal, power supply voltage is not applied to the IG2 terminal, and +BI1 terminal voltage is 9.5 V or more for 4 seconds or more.

  • INF Code: 87


    • Open or short in IG1 circuit

    • Improperly connected connector, deformation or corrosion of terminals

    • IG start circuit (for power source mode)

    • Auxiliary battery

    • Hybrid control system (Charging circuit)

    • Skid control ECU assembly

  • INF Code: 88


    • Open or short in IG2 circuit

    • Improperly connected connector, deformation or corrosion of terminals

    • IG start circuit (for power source mode)

    • Auxiliary battery

    • Hybrid control system (Charging circuit)

    • Skid control ECU assembly

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Table 1. DTC Detection Conditions: C1241 INF Code: 81
  Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4 Pattern 5 Pattern 6
Diagnosis Condition When the ABS main relay 1 is on and the relay contact is on, the relay power supply terminal (BS01) voltage is less than 8.9 V ○ ○ - - - -
When 0.05 seconds or more elapse after the ABS main relay 1 is turned on and the relay contact is on, the relay power supply terminal (BS01) voltage is less than 8.9 V - - ○ - - -
While the ABS main relay 1 is on, the ECU starting power supply input terminal (+BI and +BI3) voltage is less than 9.1 V - - - ○ - -
The pressure sensor power supply voltage (VCM) is 4.7 V or less - - - - ○ -
The pressure sensor power supply voltage (VCM) is 5.3 V or more - - - - - ○
Malfunction Status The actual current does not reach the target value for any of the linear solenoids supplied by the relay ○ - - - - -
The brake pedal is not depressed - ○ - - - -
When brake control is prohibited for even one wheel while the brake pedal is depressed - - ○ - - -
Relay contact is off - - - ○ - -
The voltage of the ECU starting power supply input terminal (+BI and +BI3) of the relevant system is 9.1 V or less - - - - ○ ○
Detection Time 0.03 seconds or more 3 seconds or more - 0.2 seconds or more 0.05 seconds or more 0.05 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip 1 trip
  Vehicle Condition
Pattern 7 Pattern 8 Pattern 9 Pattern 10 Pattern 11 Pattern 12
Diagnosis Condition   - - - - - -
Malfunction Status The brake pedal stroke sensor output voltage 1 (SKS) terminal voltage is less than 0.26 V ○ - - - - -
The brake pedal stroke sensor output voltage 2 (SKS2) terminal voltage is less than 0.26 V - ○ - - - -
The brake pedal stroke sensor output voltage 1 (SKS) terminal voltage is 4.89 V or more - - ○ - - -
The brake pedal stroke sensor output voltage 2 (SKS2) terminal voltage is 4.89 V or more - - - ○ - -
The brake pedal stroke sensor power supply voltage (VCSK) terminal voltage is 4.67 V or less - - - - ○ -
The brake pedal stroke sensor power supply voltage (VCSK) terminal voltage is 5.41 V or more - - - - - ○
Detection Time 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip 1 trip
Table 2. DTC Detection Conditions: C1241 INF Code: 82
  Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4 Pattern 5 Pattern 6
Diagnosis Condition When the ABS main relay 2 is on and the relay contact is on, the relay power supply terminal (BS02) voltage is less than 8.9 V ○ ○ - - - -
When 0.05 seconds or more elapse after the ABS main relay 2 is turned on and the relay contact is on, the relay power supply terminal (BS02) voltage is less than 8.9 V - - ○ - - -
While the ABS main relay 2 is on, the ECU starting power supply input terminal (+B2 and +BI4) voltage is less than 9.1 V - - - ○ - -
The pressure sensor power supply voltage (VCM2) is 4.7 V or less - - - - ○ -
The pressure sensor power supply voltage (VCM2) is 5.3 V or more - - - - - ○
Malfunction Status The actual current does not reach the target value for any of the linear solenoids supplied by the relay ○ - - - - -
The brake pedal is not depressed - ○ - - - -
When brake control is prohibited for even one wheel while the brake pedal is depressed - - ○ - - -
Relay contact is off - - - ○ - -
The voltage of the ECU starting power supply input terminal (+B2 and +BI4) of the relevant system is 9.1 V or less - - - - ○ ○
Detection Time 0.03 seconds or more 3 seconds or more - 0.2 seconds or more 0.05 seconds or more 0.05 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip 1 trip
  Vehicle Condition
Pattern 7 Pattern 8 Pattern 9 Pattern 10 Pattern 11 Pattern 12
Diagnosis Condition   - - - - - -
Malfunction Status The brake pedal stroke sensor output voltage 1 (SKS) terminal voltage is less than 0.26 V ○ - - - - -
The brake pedal stroke sensor output voltage 2 (SKS2) terminal voltage is less than 0.26 V - ○ - - - -
The brake pedal stroke sensor output voltage 1 (SKS) terminal voltage is 4.89 V or more - - ○ - - -
The brake pedal stroke sensor output voltage 2 (SKS2) terminal voltage is 4.89 V or more - - - ○ - -
The brake pedal stroke sensor power supply voltage (VCSK) terminal voltage is 4.67 V or less - - - - ○ -
The brake pedal stroke sensor power supply voltage (VCSK) terminal voltage is 5.41 V or more - - - - - ○
Detection Time 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more 0.2 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip 1 trip
Table 3. DTC Detection Conditions: C1241 INF Code: 91, 92
  Vehicle Condition
Pattern 1 Pattern 2 Pattern 3 Pattern 4 Pattern 5 Pattern 6
Diagnosis Condition The IG1 terminal voltage is 3.5 V or more and the vehicle speed is 3 km/h or more ○ - ○ ○ - -
The IG2 terminal voltage is 3.5 V or more and the vehicle speed is 3 km/h or more - ○ - - ○ ○
Malfunction Status The IG1+ terminal voltage is 9.5 V or less ○ ○ - - - -
The +BI1 and +BI3 terminal voltage is 9.1 V or less - - ○ - ○ -
The +BI2 and +BI4 terminal voltage is 9.1 V or less - - - ○ - ○
Detection Time 10 seconds or more 10 seconds or more 10 seconds or more 10 seconds or more 10 seconds or more 10 seconds or more
Number of Trips 1 trip 1 trip 1 trip 1 trip 1 trip 1 trip
Table 4. DTC Detection Conditions: C1241 INF Code: 93, 94
  Vehicle Condition
Pattern 1 Pattern 2
Diagnosis Condition The IG1 terminal voltage is 3.5 V or more and the +BI1 and +BI3 terminal voltage is 9. 1 V or less ○ -
The IG2 terminal voltage is 3.5 V or more and the +BI2 and +BI4 terminal voltage is 9. 1 V or less - ○
Malfunction Status Both the front wheel RH and rear wheel LH wheel speed sensor power supply voltage is low ○ -
Both the front wheel LH and rear wheel RH wheel speed sensor power supply voltage is low - ○
Detection Time 60 seconds or more 60 seconds or more
Number of Trips 1 trip 1 trip
Figure 2. for RHD: B004R4KE18
Figure 1. for LHD: B004R4KE17
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WIRING DIAGRAM

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CAUTION / NOTICE / HINT

Note:

  • When replacing the skid control ECU assembly, perform initialization and calibration of the linear solenoid valve.

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  • Inspect the fuses for circuits related to this system before performing the following procedure.

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PROCEDURE


  1. Click here

    CHECK HYBRID CONTROL SYSTEM


    1. Check if hybrid control system DTCs are output.

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      1. Powertrain > Hybrid Control > Trouble Codes


      Result
      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

  2. Click here

    CHECK DTC


    1. Check that no ABS main relay, brake pedal stroke sensor and/or brake control power supply with bracket assembly malfunction DTCs are output.

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      1. Chassis > ABS/VSC/TRC > Trouble Codes


      Result
      Result Proceed to
      ABS main relay and brake control power supply with bracket assembly malfunction DTCs are not output. A
      ABS main relay and/or brake control power supply with bracket assembly malfunction DTCs are output. B

  3. Click here

    CHECK AUXILIARY BATTERY


    1. Check the auxiliary battery voltage.

      Standard Voltage
      Tester Connection Condition Specified Condition
      Auxiliary battery Power switch on (IG) 11 to 14 V
      Auxiliary battery Power switch on (READY) 11 to 15.5 V
      Result
      Proceed to
      OK
      NG

    • OKClick here
    • NG

      CHARGE OR REPLACE AUXILIARY BATTERY

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    CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.

    2. Disconnect the A11, A13 and A12 skid control ECU assembly connectors.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      A11-4 (+BI1) - Body ground Always 11 to 14 V
      A13-5 (+BI2) - Body ground Always 11 to 14 V
      A11-5 (+BI3) - Body ground Always 11 to 14 V
      A13-6 (+BI4) - Body ground Always 11 to 14 V
      A11-2 (IG1) - Body ground Power switch on (IG) 11 to 14 V
      A12-5 (IG2) - Body ground Power switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

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    CHECK HARNESS AND CONNECTOR (GND TERMINAL)


    1. Turn the power switch off.

    2. Make sure that there is no looseness at the locking part and the connecting part of the connector.

    3. Disconnect the A10 skid control ECU assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A10-1 (GND) - Body ground Always Below 1 Ω
      A11-3 (GND2) - Body ground Always Below 1 Ω
      A11-1 (GND3) - Body ground Always Below 1 Ω
      A12-3 (GND4) - Body ground Always Below 1 Ω
      A12-1 (GND5) - Body ground Always Below 1 Ω
      A13-3 (GND6) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    • OKClick here
    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)

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    RECONFIRM DTC


    1. Reconnect the A11, A13, A10 and A12 skid control ECU assembly connectors.

    2. Clear the DTCs.

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      1. Chassis > ABS/VSC/TRC > Clear DTCs


    3. Turn the power switch off.

    4. Turn the power switch on (IG).

    5. Check if the same DTC is output.

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      1. Chassis > ABS/VSC/TRC > Trouble Codes


      Result
      Result Proceed to
      DTCs C1241 and C1242 are not output. A
      DTCs C1241 and/or C1242 are output. B

    • A

      USE SIMULATION METHOD TO CHECKClick here

    • B

      REPLACE SKID CONTROL ECU ASSEMBLY for LHD:Click here

      REPLACE SKID CONTROL ECU ASSEMBLY for RHD:Click here