ANTI-LOCK BRAKE SYSTEM, Diagnostic DTC:C1277, C1278, C1415, C1416

DTC Code DTC Name
C1277 Abnormal Change in Output Signal of Rear Speed Sensor RH (Test Mode DTC)
C1278 Abnormal Change in Output Signal of Rear Speed Sensor LH (Test Mode DTC)
C1415 Rear Speed Sensor RH Output Malfunction
C1416 Rear Speed Sensor LH Output Malfunction

DESCRIPTION

Refer to DTCs C1273, C1274, C1403 and C1404.

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DTC No. Detection Item DTC Detection Condition Trouble Area
C1277 Abnormal Change in Output Signal of Rear Speed Sensor RH (Test Mode DTC) Detected only during Test Mode.

  • Rear speed sensor RH

  • Rear skid control rotor RH (Rear axle shaft bearing RH)
C1278 Abnormal Change in Output Signal of Rear Speed Sensor LH (Test Mode DTC) Detected only during Test Mode.

  • Rear speed sensor LH

  • Rear skid control rotor LH (Rear axle shaft bearing LH)
C1415 Rear Speed Sensor RH Output Malfunction

Either of the following 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.

  • Rear speed sensor RH

  • Rear skid control rotor RH (Rear axle shaft bearing RH)

  • Sensor installation

  • Skid control ECU (Brake actuator assembly)

  • Wire harness or connector
C1416 Rear Speed Sensor LH Output Malfunction

Either of the following 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.

  • Rear speed sensor LH

  • Rear skid control rotor LH (Rear axle shaft bearing LH)

  • Sensor installation

  • Skid control ECU (Brake actuator assembly)

  • Wire harness or connector

WIRING DIAGRAM

Refer to DTCs C1407 and C1408.

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CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake actuator assembly), perform Test Mode (Signal Check) to acquire the rear differential lock identification information.

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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 the DTC.

      Click here


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      RR Speed Open Rear speed sensor RH open detection Normal or Error Normal Error: Momentary interruption
      RL Speed Open Rear speed sensor LH open detection Normal or Error Normal Error: Momentary interruption

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      RR Speed Open
      RL Speed Open

      Tech Tips

      Perform the above inspection before removing the sensor and connector.

      OK
      Normal (There are no momentary interruptions.)
      Result
      Proceed to
      OK
      NG

    NG

    CHECK REAR SPEED SENSOR INSTALLATION Click here

    OK

  2. READ VALUE USING GTS (REAR SPEED SENSOR)


    1. Connect the GTS to the DLC3.

    2. Start the engine.

    3. Turn the GTS on.

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

    5. According to the display on the GTS, read the Data List.


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      RR Wheel Speed Rear wheel speed sensor RH reading

      Min.: 0 km/h (0 mph)

      Max.: 326.4 km/h (202 mph)

      		 Vehicle stopped: 0 km/h (0 mph)

      When driving at constant speed:

      No large fluctuations
      RL Wheel Speed Rear wheel speed sensor LH reading

      Min.: 0 km/h (0 mph)

      Max.: 326.4 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
      RR Wheel Speed
      RL Wheel Speed

    6. Check that there is no difference between the speed value output from the speed sensor displayed on the GTS and the speed value displayed on the speedometer when driving the vehicle.

      Tech Tips

      Factors that affect the indicated vehicle speed include tire size, tire inflation 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 here

      OK
      The speed value output from the speed sensor displayed on the GTS is the same as the actual vehicle speed measured using a speedometer tester (calibrated chassis dynamometer).

      Note

      Check the speed sensor signal after replacement.

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      Tech Tips

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

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      Result
      Proceed to
      OK
      NG

    NG

    GO TO STEP 4 Click here

    OK

  3. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    2. Turn the engine switch off.

    3. Start the engine.

    4. Perform a road test

    5. Check if the same DTC is recorded.

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      Chassis > ABS/VSC/TRC > Trouble Codes
      Result
      Proceed to
      DTCs C1415 and C1416 are not output
      DTCs C1415 and/or C1416 are output

    DTCs C1415 and C1416 are not output

    USE SIMULATION METHOD TO CHECK Click here

    DTCs C1415 and/or C1416 are output

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  4. CHECK REAR SPEED SENSOR INSTALLATION


    1. Turn the engine switch off.

    2. B003R2YC14
      *a Normal
      *b Abnormal
      *c Clearance

      Check the rear speed sensor installation.

      Click here

      OK
      There is no clearance between the sensor and the rear axle housing.
      The installation bolt is tightened properly.
      Result
      Proceed to
      OK
      NG

    NG

    INSTALL REAR SPEED SENSOR CORRECTLY Click here

    OK

  5. INSPECT REAR SPEED SENSOR TIP


    1. Remove the rear speed sensor.

      Click here

    2. Check the speed sensor tip.

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

      Note


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

      • If there is iron powder sticking to the rotor, this will result in a malfunction, so confirm that the rotor is not contaminated with foreign material before replacing the sensor.

      • Check the speed sensor signal after cleaning or replacement.

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      Result
      Proceed to
      OK
      NG

    NG

    CLEAN OR REPLACE REAR SPEED SENSOR

    OK

  6. INSPECT REAR AXLE SHAFT BEARING


    1. Remove the rear axle shaft bearing.

      for Rear Disc Brake: Click here

      for Rear Drum Brake: Click here

    2. Check the rear skid control rotor.

      OK
      No scratches, oil, or foreign matter on the rotors.

      Note

      Check the speed sensor signal after cleaning or replacement.

      Click here

      Tech Tips


      • The rear skid control rotor is incorporated into the rear axle shaft bearing.

      • If the rear skid control rotor needs to be replaced, replace it together with the rear axle shaft bearing.

    3. Reinstall the rear speed sensor and rear axle shaft bearing.

      for the rear speed sensor: Click here

      for the rear axle shaft bearing (for Rear Disc Brake): Click here

      for the rear axle shaft bearing (for Rear Drum Brake): Click here

      Result
      Proceed to
      OK
      NG

    NG

    CLEAN OR REPLACE REAR AXLE SHAFT BEARING

    OK

  7. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - REAR SPEED SENSOR)


    1. Turn the engine switch off.

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

    3. Disconnect the A68 skid control ECU (brake actuator assembly) connector and the O8 and/or O9 rear speed sensor connector.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      A68-17 (RR+) - O8-2 (RR+) Always Below 1 Ω
      A68-16 (RR-) - O8-1 (RR-) Always Below 1 Ω
      A68-17 (RR+) or O8-2 (RR+) - Body ground Always 10 kΩ or higher
      A68-16 (RR-) or O8-1 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A68-5 (RL+) - O9-2 (RL+) Always Below 1 Ω
      A68-4 (RL-) - O9-1 (RL-) Always Below 1 Ω
      A68-5 (RL+) or O9-2 (RL+) - Body ground Always 10 kΩ or higher
      A68-4 (RL-) or O9-1 (RL-) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. INSPECT BRAKE ACTUATOR ASSEMBLY (SENSOR INPUT)


    1. Reconnect the A68 skid control ECU (brake actuator assembly) connector.

    2. Turn the engine switch on (IG).

    3. B003PA4C08
      *A for RH
      *B for LH
      *a

      Front view of wire harness connector

      (to Rear Speed Sensor)

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

      Standard Voltage
      for RH
      Tester Connection Switch Condition Specified Condition
      O8-2 (RR+) - Body ground Engine switch on (IG) 8 to 14 V
      for LH
      Tester Connection Switch Condition Specified Condition
      O9-2 (RL+) - Body ground Engine switch on (IG) 8 to 14 V

      Note

      Check the speed sensor signal after replacement.

      Click here

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE REAR SPEED SENSOR Click here

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here