ANTI-LOCK BRAKE SYSTEM(for Type B), Diagnostic DTC:C1271,C1272,C1275,C1276,C1413 and C1414

DTC Code DTC Name
C1271 Low Output Signal of Front Speed Sensor RH (Test Mode DTC)
C1272 Low Output Signal of Front Speed Sensor LH (Test Mode DTC)
C1275 Abnormal Change in Output Signal of Front Speed Sensor RH (Test Mode DTC)
C1276 Abnormal Change in Output Signal of Front Speed Sensor LH (Test Mode DTC)
C1413 Front Speed Sensor RH Output Malfunction
C1414 Front Speed Sensor LH Output Malfunction

DESCRIPTION

Each speed sensor detects wheel speed and sends signals to the skid control ECU (brake actuator assembly). These signals are used by the ABS.

The speed sensor rotors have 48 serrations. Hall IC type speed sensors use the frequency of output pulses to detect the vehicle speed. Because the sensor outputs digital pulses, it can detect the vehicle speed even when the vehicle is nearly stationary.

DTCs C1271, C1272, C1275 and C1276 are cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs C1271, C1272, C1275 and C1276 are output only in Test Mode.

C223506E01
Tip:

Check the connection status between the sensor connector and the vehicle wire harness.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

C1271

Low Output Signal of Front Speed Sensor RH (Test Mode DTC)

Detected only during Test Mode.

  • Front speed sensor RH

  • Sensor installation

  • Front speed sensor rotor RH (Front axle hub sub-assembly RH)

C1272

Low Output Signal of Front Speed Sensor LH (Test Mode DTC)

Detected only during Test Mode.

  • Front speed sensor LH

  • Sensor installation

  • Front speed sensor rotor LH (Front axle hub sub-assembly LH)

C1275

Abnormal Change in Output Signal of Front Speed Sensor RH (Test Mode DTC)

Detected only during Test Mode.

Front speed sensor rotor RH (Front axle hub sub-assembly RH)

C1276

Abnormal Change in Output Signal of Front Speed Sensor LH (Test Mode DTC)

Detected only during Test Mode.

Front speed sensor rotor LH (Front axle hub sub-assembly LH)

C1413

Front Speed Sensor RH Output Malfunction

Any of the following conditions is detected:

  1. An open in the sensor signal circuit of a malfunctioning area occurs 255 times or more.

  2. At a vehicle speed of 20 km/h (12 mph) or more, noise occurs in the sensor signals of a malfunctioning wheel 75 times or more within 5 seconds.

  3. At a vehicle speed of 10 km/h (6 mph) or more, noise occurs once per rotor rotation for 15 seconds or more.

  • Front speed sensor RH

  • Speed sensor circuit

  • Sensor installation

  • Front speed sensor rotor RH (Front axle hub sub-assembly RH)

  • Skid control ECU (Brake actuator assembly)

C1414

Front Speed Sensor LH Output Malfunction

Any of the following conditions is detected:

  1. An open in the sensor signal circuit of a malfunctioning area occurs 255 times or more.

  2. At a vehicle speed of 20 km/h (12 mph) or more, noise occurs in the sensor signals of a malfunctioning wheel 75 times or more within 5 seconds.

  3. At a vehicle speed of 10 km/h (6 mph) or more, noise occurs once per rotor rotation for 15 seconds or more.

  • Front speed sensor LH

  • Speed sensor circuit

  • Sensor installation

  • Front speed sensor rotor LH (Front axle hub sub-assembly LH)

  • Skid control ECU (Brake actuator assembly)
Tip:

for C1413 and C1414: Even after the trouble areas are repaired, the ABS warning light will not go off unless the following operations are performed.

  1. Drive the vehicle at 20 km/h (12 mph) for 30 seconds or more and check that the ABS warning light goes off.

  2. Clear the DTCs.

Tip:

  • DTC C1413 is for the front speed sensor RH.

  • DTC C1414 is for the front speed sensor LH.

WIRING DIAGRAM

C243493E69

PROCEDURE

  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)

    1. Using the GTS, check for any momentary interruption in the wire harness and connector corresponding to a DTC.

      Click here

      Chassis > ABS/VSC/TRC > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      FR Speed Open

      Front speed sensor RH open detection

      Error or Normal

      Error: Momentary interruption

      Normal: Normal

      -

      FL Speed Open

      Front speed sensor LH open detection

      Error or Normal

      Error: Momentary interruption

      Normal: Normal

      -

      Chassis > ABS/VSC/TRC > Data List

      Tester Display

      FR Speed Open

      FL Speed Open

      OK

      There are no momentary interruptions.

      Tip:

      Perform the above inspection before removing the sensor and connector.

    Result

    Proceed to

    OK

    NG
    NG

    CHECK FRONT SPEED SENSOR INSTALLATIONClick here

    OK

  2. READ VALUE USING GTS (FRONT SPEED SENSOR)

    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Start the engine.

    4. Select the Data List using the GTS.

      Click here

      Chassis > ABS/VSC/TRC > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      FR Wheel Speed

      Front wheel speed sensor RH reading

      Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)

      Vehicle stopped: 0 km/h (0 mph)

      When driving at constant speed: No large fluctuations

      FL Wheel Speed

      Front wheel speed sensor LH reading

      Min.: 0 km/h (0 mph), Max.: 326 km/h (202 mph)

      Vehicle stopped: 0 km/h (0 mph)

      When driving at constant speed: No large fluctuations

      Chassis > ABS/VSC/TRC > Data List

      Tester Display

      FR Wheel Speed

      FL Wheel Speed

    5. Check the speed value output from the speed sensor displayed on the GTS.

      Tip:

      Factors that affect the indicated vehicle speed include tire size, tire pressure, and tire wear. The speed indicated on the speedometer has an allowable margin of error. This can be tested using a speedometer tester (calibrated chassis dynamometer). For details about testing and the margin of error, see the reference chart.

      Click hereClick here

      OK

      The speed value output from the speed sensor displayed on the GTS is similar to the speed indicated on the speedometer.

    Result

    Proceed to

    OK

    NG
    NG

    CHECK FRONT SPEED SENSOR INSTALLATIONClick here

    OK

  3. RECONFIRM DTC

    1. Turn the ignition switch off.

    2. Clear the DTCs.

      Click here

      Chassis > ABS/VSC/TRC > Clear DTCs

    3. Turn the ignition switch off.

    4. Start the engine.

    5. Perform a road test.

    6. Check if the same DTC is output.

      Click here

      Chassis > ABS/VSC/TRC > Trouble Codes

      Result

      Result

      Proceed to

      DTCs C1413 and C1414 are not output.

      A

      DTCs C1413 and/or C1414 are output.

      B
      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.

      Click here

    A

    USE SIMULATION METHOD TO CHECK

    Click hereClick hereClick here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY

    Click hereClick here

  4. CHECK FRONT SPEED SENSOR INSTALLATION

    1. C168336C10

      *1

      Front Speed Sensor

      *a

      Correct

      *b

      Incorrect

      *c

      8.5 Nm

      *d

      No clearance

      Check the speed sensor installation.

      OK

      There is no clearance between the sensor and the front steering knuckle.

      The installation bolt is tightened properly.

      Torque

      8.5 N*m (87 kgf*cm, 75 in.*lbf)

    Result

    Proceed to

    OK

    NG
    NG

    INSTALL FRONT SPEED SENSOR CORRECTLY

    Click here

    OK

  5. CHECK FRONT SPEED SENSOR AND SENSOR ROTOR

    1. Remove the front speed sensor and the component with the sensor rotor.

      for speed sensor:Click here

      for sensor rotor:Click hereClick here

    2. Check the speed sensor tip and speed sensor rotor.

      OK

      No scratches, oil, or foreign matter on the sensor tip and rotor.

      Note:

      • If no damage to the speed sensor tip is found during this inspection, do not replace the speed sensor.

        If there are any ferrous metal filings stuck to the rotor, this will result in a malfunction, so confirm that the rotor is not contaminated with foreign matter before replacing the sensor.

      • Check the speed sensor signal after cleaning or replacement.

        Click here

    Result

    Proceed to

    OK

    NG
    NG

    CLEAN OR REPLACE FRONT SPEED SENSOR OR COMPONENT WITH SENSOR ROTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - FRONT SPEED SENSOR)

    1. Install the front speed sensor and the component with the sensor rotor.

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

    3. Disconnect the A124 skid control ECU (brake actuator assembly) connector.

    4. Disconnect A157 or A158 front speed sensor connector.

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

      Standard Resistance

      Table 1. for RH

      Tester Connection

      Condition

      Specified Condition

      A124-7 (FR+) - A157-1 (FR+)

      Always

      Below 1 Ω

      A124-7 (FR+) or A157-1 (FR+) - Body ground

      Always

      10 kΩ or higher

      A124-6 (FR-) - A157-2 (FR-)

      Always

      Below 1 Ω

      A124-6 (FR-) or A157-2 (FR-) - Body ground

      Always

      10 kΩ or higher
      Table 2. for LH

      Tester Connection

      Condition

      Specified Condition

      A124-19 (FL+) - A158-1 (FL+)

      Always

      Below 1 Ω

      A124-19 (FL+) or A158-1 (FL+) - Body ground

      Always

      10 kΩ or higher

      A124-18 (FL-) - A158-2 (FL-)

      Always

      Below 1 Ω

      A124-18 (FL-) or A158-2 (FL-) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  7. INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR INPUT)

    1. C156480C26

      *a

      Front view of wire harness connector

      (to Front Speed Sensor)

      Reconnect the A124 skid control ECU (brake actuator assembly) connector.

    2. Turn the ignition switch to ON.

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

      Standard Voltage

      Table 3. for RH

      Tester Connection

      Condition

      Specified Condition

      A157-1 (FR+) - Body ground

      Ignition switch ON

      5.7 to 14 V
      Table 4. for LH

      Tester Connection

      Condition

      Specified Condition

      A158-1 (FL+) - Body ground

      Ignition switch ON

      5.7 to 14 V
      Note:

      Check the speed sensor signal after replacement.

      Click here

      Tip:

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step before replacing parts.

      Click here

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE FRONT SPEED SENSOR

    Click here

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY

    Click hereClick here