VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1273, C1274, C1277, C1278, C1415, C1416

DTC Code DTC Name
C1273 Low Output Signal of Rear Speed Sensor RH (Test Mode DTC)
C1274 Low Output Signal of Rear Speed Sensor LH (Test Mode DTC)
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

Each speed sensor detects the 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 rows of alternating N and S magnetic poles.

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 C1273, C1274, C1277 and C1278 are cleared when the speed sensor sends a vehicle speed signal or when Test Mode ends. DTCs C1273, C1274, C1277 and C1278 are output only in Test Mode.

B003WCOE06

Tech Tips

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

DTC No. Detection Item DTC Detection Condition Trouble Area
C1273 Low Output Signal of Rear Speed Sensor RH (Test Mode DTC) Detected only during Test Mode.

  • Rear speed sensor RH

  • Sensor installation

  • Rear speed sensor rotor RH (rear axle hub and bearing assembly RH)
C1274 Low Output Signal of Rear Speed Sensor LH (Test Mode DTC) Detected only during Test Mode.

  • Rear speed sensor LH

  • Sensor installation

  • Rear speed sensor rotor LH (rear axle hub and bearing assembly LH)
C1277 Abnormal Change in Output Signal of Rear Speed Sensor RH (Test Mode DTC) Detected only during Test Mode. Rear speed sensor rotor RH (rear axle hub and bearing assembly RH)
C1278 Abnormal Change in Output Signal of Rear Speed Sensor LH (Test Mode DTC) Detected only during Test Mode. Rear speed sensor rotor LH (rear axle hub and bearing assembly LH)
C1415 Rear Speed Sensor RH Output Malfunction

Any 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

  • Speed sensor circuit

  • Sensor installation

  • Rear speed sensor rotor RH (rear axle hub and bearing assembly RH)

  • Skid control ECU (brake actuator assembly)
C1416 Rear Speed Sensor LH Output Malfunction

Any 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

  • Speed sensor circuit

  • Sensor installation

  • Rear speed sensor rotor LH (rear axle hub and bearing assembly LH)

  • Skid control ECU (brake actuator assembly)

Tech Tips

for C1415 and C1416: 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 30 km/h (19 mph) for 30 seconds or more and check that the ABS warning light goes off.

  2. Clear the DTCs.

Tech Tips


  • DTC C1415 is for the rear speed sensor RH.

  • DTC C1416 is for the rear speed sensor LH.

WIRING DIAGRAM

B003VSZE21
*a Rear Speed Sensor RH
*b Rear Speed Sensor LH
*c Skid Control ECU (Brake Actuator Assembly)

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake actuator assembly), perform zero point calibration and store system information.

Click here

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
      RR Speed Open Rear speed sensor RH open detection Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      RL Speed Open Rear speed sensor LH open detection Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      RR Speed Open
      RL Speed Open
      OK
      There are no momentary interruptions.

      Tech Tips

      Perform the above inspection before removing the sensor and connector.

      Result
      Proceed to
      OK
      NG

    NG

    GO TO STEP 4 Click here

    OK

  2. READ VALUE USING GTS (REAR SPEED SENSOR)


    1. Turn the engine 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
      RR Wheel Speed Rear 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
      RL Wheel Speed Rear 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
      RR Wheel Speed
      RL Wheel Speed

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

      Tech Tips

      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 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 REAR SPEED SENSOR INSTALLATION Click here

    OK

  3. RECONFIRM DTC


    1. Turn the engine switch off.

    2. Clear the DTCs.

      Click here


      Chassis > ABS/VSC/TRC > Clear DTCs

    3. Turn the engine 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 C1415 and C1416 are not output. A
      DTCs C1415 and/or C1416 are output. B

      Tech Tips

      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 here

    B

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here

  4. CHECK REAR SPEED SENSOR INSTALLATION


    1. Turn the engine switch off.

    2. B003VL6C10
      *1 Rear 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 rear axle carrier.
      The installation bolt is tightened properly.
      Torque
      8.5 N*m (87 kgf*cm, 75 in.*lbf)
      Result
      Proceed to
      OK
      NG

    NG

    INSTALL REAR SPEED SENSOR CORRECTLY Click here

    OK

  5. CHECK REAR SPEED SENSOR AND SENSOR ROTOR


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

      for speed sensor: Click here

      for sensor rotor: Click 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 REAR SPEED SENSOR OR COMPONENT WITH SENSOR ROTOR

    OK

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


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

    2. Disconnect the A15 skid control ECU (brake actuator assembly) connector.

    3. Disconnect the P19 or Q28 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
      A15-17 (RR+) - P19-1 (RR+) Always Below 1 Ω
      A15-17 (RR+) - Body ground Always 10 kΩ or higher
      P19-1 (RR+) - Body ground Always 10 kΩ or higher
      A15-16 (RR-) - P19-2 (RR-) Always Below 1 Ω
      A15-16 (RR-) - Body ground Always 10 kΩ or higher
      P19-2 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A15-5 (RL+) - Q28-1 (RL+) Always Below 1 Ω
      A15-5 (RL+) - Body ground Always 10 kΩ or higher
      Q28-1 (RL+) - Body ground Always 10 kΩ or higher
      A15-4 (RL-) - Q28-2 (RL-) Always Below 1 Ω
      A15-4 (RL-) - Body ground Always 10 kΩ or higher
      Q28-2 (RL-) - 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. B003UF1C19
      *a

      Front view of wire harness connector

      (to Rear Speed Sensor)

      Reconnect the A15 skid control ECU (brake actuator assembly) connector.

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      for RH
      Tester Connection Condition Specified Condition
      P19-1 (RR+) - Body ground Engine switch on (IG) 5.7 to 14 V
      for LH
      Tester Connection Condition Specified Condition
      Q28-1 (RL+) - Body ground Engine switch on (IG) 5.7 to 14 V

      Note

      Check the speed sensor signal after replacement.

      Click here

      Tech Tips

      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 REAR SPEED SENSOR Click here

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY for LHD: Click here
    REPLACE BRAKE ACTUATOR ASSEMBLY for RHD: Click here