VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1407, C1408

DTC Code DTC Name
C1407 Open or Short in Rear Speed Sensor RH Circuit
C1408 Open or Short in Rear Speed Sensor LH Circuit

DESCRIPTION

The speed sensor detects wheel speed and sends the appropriate signals to the skid control ECU. These signals are used for ABS control.

Speed sensor rotors have rows of alternating N and S magnetic poles, and their magnetic fields change when the rotors turn.

Each speed sensor detects that magnetic change and sends a pulse signal to the skid control ECU.

Tech Tips

The output voltage values shown below are those when the skid control ECU and the speed sensors are connected to the vehicle harness.

A019MK6E01
DTC Code DTC Detection Condition Trouble Area

C1407

C1408

Either of the following is detected:


  1. An open in the speed sensor signal circuit continues for 0.5 seconds or more.

  2. With the IG1 terminal voltage 9.5 V or more, the sensor power supply voltage decreases for 0.5 seconds or more.

  • Rear speed sensor RH/LH

  • Speed sensor circuit

  • Brake actuator assembly (Skid control ECU)

Tech Tips


  • DTC C1407 is for the rear speed sensor RH.

  • DTC C1408 is for the rear speed sensor LH.

WIRING DIAGRAM

Refer to DTCs C1403 and C1404 Click here.

INSPECTION PROCEDURE

Note

When replacing the brake actuator assembly, perform zero point calibration and store system information Click here.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION)


    1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to the DTC Click here.

      ABS/VSC/TRC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      RR Speed Open RR speed sensor open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      RL Speed Open RL speed sensor open detection / Error or Normal

      Error: Momentary interruption

      Normal: Normal

      		 -
      Result
      Result Proceed to
      There are no momentary interruptions A
      There are momentary interruptions (for 2WD) B
      There are momentary interruptions (for AWD) C

      Tech Tips

      Perform the above inspection before removing the sensor and connector.


    B

    CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE) Click here

    C

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR) Click here

    A

  2. READ VALUE USING INTELLIGENT TESTER (REAR SPEED SENSOR)


    1. Turn the engine switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Start the engine.

    4. Select the Data List on the intelligent tester Click here.

      ABS/VSC/TRC
      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

    5. Check that the speed value output from the speed sensor displayed on the intelligent tester.

      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 intelligent tester is the similar speed as indicated on the speedometer.
      Result
      Result Proceed to
      OK A
      NG (for 2WD) B
      NG (for AWD) C

    B

    CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE) Click here

    C

    CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR) Click here

    A

  3. RECONFIRM DTC


    1. Turn the engine switch off.

    2. Clear the DTCs Click here.

    3. Start the engine.

    4. Drive the vehicle at a speed of 40 km/h (25 mph) or more for at least 60 seconds.

    5. Check if the same DTC is recorded Click here.

      Result
      Result Proceed to
      DTCs (C1407 and C1408) are not output A
      DTCs (C1407 and/or C1408) 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 Click here.


    B

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

  4. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE)


    1. A019L74E01
      Text in Illustration
      *1 Skid Control Sensor Wire
      *2 for RH
      *3 Sensor Side Connector "A"
      *4 Vehicle Side Connector "B"
      *5 for LH
      *6 Sensor Side Connector "A"
      *7 Vehicle Side Connector "B"

      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 skid control sensor wire.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      A-2 - B-2 Always Below 1 Ω
      A-2 - B-1 Always 10 kΩ or higher
      A-2 - Body ground Always 10 kΩ or higher
      A-1 - B-1 Always Below 1 Ω
      A-1 - B-2 Always 10 kΩ or higher
      A-1 - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A-2 - B-3 Always Below 1 Ω
      A-2 - B-1 Always 10 kΩ or higher
      A-2 - Body ground Always 10 kΩ or higher
      A-1 - B-1 Always Below 1 Ω
      A-1 - B-3 Always 10 kΩ or higher
      A-1 - Body ground Always 10 kΩ or higher

      Note

      Check the speed sensor signal after replacement Click here.


    NG

    REPLACE SKID CONTROL SENSOR WIRE

    OK

  5. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - REAR SPEED SENSOR)


    1. A019PL0E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)
      *2

      Front view of wire harness connector

      (to Rear Speed Sensor)

      Turn the engine switch off.

    2. Reconnect the skid control sensor wire (for 2WD).

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

    4. Disconnect the skid control ECU connector and the rear speed sensor connector.

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

      Standard Resistance
      for RH
      Tester Connection Condition Specified Condition
      A44-17 (RR+) - R3-2 (RR+) Always Below 1 Ω
      A44-17 (RR+) - Body ground Always 10 kΩ or higher
      A44-16 (RR-) - R3-1 (RR-) Always Below 1 Ω
      A44-16 (RR-) - Body ground Always 10 kΩ or higher
      for LH
      Tester Connection Condition Specified Condition
      A44-5 (RL+) - R1-3 (RL+) Always Below 1 Ω
      A44-5 (RL+) - Body ground Always 10 kΩ or higher
      A44-4 (RL-) - R1-1 (RL-) Always Below 1 Ω
      A44-4 (RL-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT SKID CONTROL ECU (SENSOR INPUT)


    1. A019P48E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Rear Speed Sensor)

      Reconnect the skid control ECU 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 Switch Condition Specified Condition
      R3-2 (RR+) - Body ground Engine switch on (IG) 8 to 14 V
      for LH
      Tester Connection Switch Condition Specified Condition
      R1-3 (RL+) - Body ground Engine switch on (IG) 8 to 14 V
      Result
      Result Proceed to
      OK (for 2WD) A
      OK (for AWD) B
      NG C

      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 Click here.


    B

    REPLACE REAR SPEED SENSOR (for AWD) Click here

    C

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    A

    REPLACE REAR SPEED SENSOR (for 2WD) Click here