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DTC C1337/91: Diameter of the Tire is not Uniform [09/2015 - 08/2019]: Procedure

  1. CHECK TIRE CONDITION 
    1. Check the size and condition of all 4 tires.

      HINT: 

      This DTC is output when tire deformation or a difference in tire size is detected.

      OK

      The diameter and air pressure of all 4 tires are the same.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    PERFORM AIR PRESSURE ADJUSTMENT OR REPLACE TIRES SO THAT ALL 4 TIRES ARE SAME IN SIZE. Refer to  INSPECTION [09/2015 - ] 

    Result: 

    OK 

    See step  2

  2. CHECK FOR DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Clear DTCs 

    2. Start the engine.
    3. Drive the vehicle at a speed of 30 km/h (19 mph) or more so that the same DTC is output.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Trouble Codes 

    4. Check if the speed sensor DTC (vehicle stability control system DTC) is output.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > ABS/VSC/TRAC/EPB > Trouble Codes 

    5. Read the DTCs using the Techstream.

      Result

      Result Proceed to
      Only DTC C1377/91 is output (w/o AVS) A
      Only DTC C1377/91 is output (w/ AVS) B
      DTCs are not output C
      Speed sensor DTCs (vehicle stability control system DTC) are output D

    Result: 

    B 

    See step  4

    Result: 

    C 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2015 - 08/2016]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 12/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 08/2019] 

    Result: 

    D 

    REPAIR CIRCUIT INDICATED BY OUTPUT CODE (VEHICLE STABILITY CONTROL SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2015 - 08/2016]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2016 - 08/2019] 

    Result: 

    A 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (SPEED SENSOR - BRAKE ACTUATOR ASSEMBLY) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Turn the engine switch off.
    3. Disconnect the A41 skid control ECU (brake actuator assembly) connector.
    4. Disconnect the A92, A93, T 1 and/or T 2 speed sensor connector (s).
    5. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      FOR FRONT RH:

      Tester Connection Condition Specified Condition
      A41-7 (FR+) - A93-3 (FR+) Always Below 1 Ω
      A41-6 (FR-) - A93-4 (FR-) Always
      A41-7 (FR+) or A93-3 (FR+) - Body ground and other terminals Always 10 kΩ or higher
      A41-6 (FR-) or A93-4 (FR-) - Body ground and other terminals Always
      FOR FRONT LH:

      Tester Connection Condition Specified Condition
      A41-22 (FL+) - A92-3 (FL+) Always Below 1 Ω
      A41-21 (FL-) - A92-4 (FL-) Always
      A41-22 (FL+) or A92-3 (FL+) - Body ground and other terminals Always 10 kΩ or higher
      A41-21 (FL-) or A92-4 (FL-) - Body ground and other terminals Always
      FOR REAR RH:

      Tester Connection Condition Specified Condition
      A41-20 (RR+) - T2-2 (RR+) Always Below 1 Ω
      A41-19 (RR-) - T2-1 (RR-) Always
      A41-20 (RR+) or T2-2 (RR+) - Body ground and other terminals Always 10 kΩ or higher
      A41-19 (RR-) or T2-1 (RR-) - Body ground and other terminals Always
      FOR REAR LH:

      Tester Connection Condition Specified Condition
      A41-5 (RL+) - T1-3 (RL+) Always Below 1 Ω
      A41-4 (RL-) - T1-1 (RL-) Always
      A41-5 (RL+) or T1-3 (RL+) - Body ground and other terminals Always 10 kΩ or higher
      A41-4 (RL-) or T1-1 (RL-) - Body ground and other terminals Always

      Result

      Proceed to
      OK
      NG
    6. Connect the A92, A93, T 1 and/or T 2 speed sensor connector (s).
    7. Connect the A41 skid control ECU (brake actuator assembly) connector.

    Result: 

    OK 

    See step  6

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

  4. CHECK HARNESS AND CONNECTOR (SKID CONTROL SENSOR WIRE - BRAKE ACTUATOR ASSEMBLY) 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Disconnect the A41 skid control ECU (brake actuator assembly) connector.
    3. Disconnect the A90, A91, T 7 and/or T 8 skid control sensor wire connector (s).
    4. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      FOR FRONT RH:

      Tester Connection Condition Specified Condition
      A41-7 (FR+) - A91-3 (FR+) Always Below 1 Ω
      A41-6 (FR-) - A91-4 (FR-) Always
      A41-7 (FR+) or A91-3 (FR+) - Body ground and other terminals Always 10 kΩ or higher
      A41-6 (FR-) or A91-4 (FR-) - Body ground and other terminals Always
      FOR FRONT LH:

      Tester Connection Condition Specified Condition
      A41-22 (FL+) - A90-3 (FL+) Always Below 1 Ω
      A41-21 (FL-) - A90-4 (FL-) Always
      A41-22 (FL+) or A90-3 (FL+) - Body ground and other terminals Always 10 kΩ or higher
      A41-21 (FL-) or A90-4 (FL-) - Body ground and other terminals Always
      FOR REAR RH:

      Tester Connection Condition Specified Condition
      A41-20 (RR+) - T7-2 (RR+) Always Below 1 Ω
      A41-19 (RR-) - T7-1 (RR-) Always
      A41-20 (RR+) or T7-2 (RR+) - Body ground and other terminals Always 10 kΩ or higher
      A41-19 (RR-) or T7-1 (RR-) - Body ground and other terminals Always
      FOR REAR LH:

      Tester Connection Condition Specified Condition
      A41-5 (RL+) - T8-3 (RL+) Always Below 1 Ω
      A41-4 (RL-) - T8-1 (RL-) Always
      A41-5 (RL+) or T8-3 (RL+) - Body ground and other terminals Always 10 kΩ or higher
      A41-4 (RL-) or T8-1 (RL-) - Body ground and other terminals Always

      Result

      Proceed to
      OK
      NG
    5. Connect the A90, A91, T 7 and/or T 8 skid control sensor wire connector (s).
    6. Connect the A41 skid control ECU (brake actuator assembly) connector.

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. INSPECT SKID CONTROL SENSOR WIRE 
    1. Make sure that there is no looseness at the locking part and the connecting part of the connectors.
    2. Turn the engine switch off.
    3. Disconnect the A90, A91, z14 and/or z15 front skid control sensor wire connector (s).
    4. Measure the resistance according to the value (s) in the table below.
      GTY646563Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A for RH *B for LH
      *1 Front Skid Control Sensor Wire - -
      *a Front view of wire harness connector
      (to Vehicle Side Connector)      		 *b Front view of wire harness connector
      (to Front Speed Sensor Side Connector)

      Standard Resistance

      FOR FRONT SKID CONTROL SENSOR WIRE RH:

      Tester Connection Condition Specified Condition
      z15-1 (FR+) - A91-3 (FR+) Always Below 1 Ω
      z15-2 (FR-) - A91-4 (FR-) Always
      z15-1 (FR+) or A91-3 (FR+) - Body ground and other terminals Always 10 kΩ or higher
      z15-2 (FR-) or A91-4 (FR-) - Body ground and other terminals Always
      FOR FRONT SKID CONTROL SENSOR WIRE LH:

      Tester Connection Condition Specified Condition
      z14-1 (FL+) - A90-3 (FL+) Always Below 1 Ω
      z14-2 (FL-) - A90-4 (FL-) Always
      z14-1 (FL+) or A90-3 (FL+) - Body ground and other terminals Always 10 kΩ or higher
      z14-2 (FL-) or A90-4 (FL-) - Body ground and other terminals Always
    5. Connect the A90, A91, z14 and/or z15 front skid control sensor wire connector (s).
    6. Disconnect the T7, T8, z22 and/or z23 rear No. 1 skid control sensor wire connector (s).
    7. Measure the resistance according to the value (s) in the table below.

      Standard Resistance

      FOR REAR NO. 1 SKID CONTROL SENSOR WIRE RH:

      Tester Connection Condition Specified Condition
      z22-1 (RR+) - T7-2 (RR+) Always Below 1 Ω
      z22-3 (RR-) - T7-1 (RR-) Always
      z22-1 (RR+) or T7-2 (RR+) - Body ground and other terminals Always 10 kΩ or higher
      z22-3 (RR-) or T7-1 (RR-) - Body ground and other terminals Always
      FOR REAR NO. 1 SKID CONTROL SENSOR WIRE LH:

      Tester Connection Condition Specified Condition
      z23-1 (RL+) - T8-3 (RL+) Always Below 1 Ω
      z23-3 (RL-) - T8-1 (RL-) Always
      z23-1 (RL+) or T8-3 (RL+) - Body ground and other terminals Always 10 kΩ or higher
      z23-3 (RL-) or T8-1 (RL-) - Body ground and other terminals Always
      GTY807254Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *1 Rear No. 1 Skid Control Sensor Wire RH
      *2 Rear No. 1 Skid Control Sensor Wire LH
      *a Front view of wire harness connector
      (to Vehicle Side Connector)
      *b Front view of wire harness connector
      (to Rear Speed Sensor Side Connector)
    8. Connect the T7, T8, z22 and/or z23 rear No. 1 skid control sensor wire connector (s).

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE SKID CONTROL SENSOR WIRE 

    Result: 

    OK 

    See step  6

  6. PERFORM TEST MODE (SIGNAL CHECK) 
    1. Turn the engine switch off.
    2. Perform the sensor check in the Test Mode procedure.

      Refer to TEST MODE PROCEDURE [09/2015 - 08/2019]

      Chassis > ABS/VSC/TRAC/EPB > Utility 

      Tester Display
      Signal Check

      OK

      All Test Mode (signal check) inspection items are normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  8

    Result: 

    OK 

    See step  7

  7. RECONFIRM DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Clear DTCs 

    2. Start the engine.
    3. Drive the vehicle at a speed of 30 km/h (19 mph) or more and check that the same DTC is output.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Trouble Codes 

      Result

      Result Proceed to
      DTC is not output A
      DTC is output B

    Result: 

    A 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2015 - 08/2016]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [08/2016 - 12/2017]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 08/2019] 

    Result: 

    B 

    REPLACE BRAKE ACTUATOR ASSEMBLY. Refer to  COMPONENTS [09/2015 - ] 

  8. CHECK SPEED SENSOR ROTOR 
    1. Turn the engine switch off.
    2. Remove the front speed sensor rotor (front axle hub sub-assembly) or rear speed sensor rotor (rear axle hub and bearing assembly).

      for Front: Refer to REMOVAL [09/2015 - 08/2019]

      for Rear: Refer to REMOVAL [09/2015 - ]

    3. Check the speed sensor rotor.

      OK

      There is no foreign matter, scratches or oil on the rotors.

      NOTE:

      Check the speed sensor signal after cleaning or replacement.

      Refer to TEST MODE PROCEDURE [09/2015 - 08/2019]

      HINT: 

      • If the front speed sensor rotor needs to be replaced, replace the front axle hub bearing assembly.
      • If the rear speed sensor rotor needs to be replaced, replace the rear axle hub and bearing assembly.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CLEAN OR REPLACE SPEED SENSOR ROTOR 

    Result: 

    OK 

    See step  9

  9. REPLACE SPEED SENSOR 
    1. Turn the engine switch off.
    2. Replace the front speed sensor or the rear speed sensor.

      for Front: Refer to REMOVAL [09/2015 - ]

      for Rear: Refer to REMOVAL [09/2015 - ]

      NOTE:

      Check the speed sensor signal after replacement.

      Refer to TEST MODE PROCEDURE [09/2015 - 08/2019]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  10

  10. RECONFIRM DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Clear DTCs 

    2. Start the engine.
    3. Drive the vehicle at a speed of 30 km/h (19 mph) or more and check that the same DTC is output.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Trouble Codes 

      Result

      Result Proceed to
      DTC is output A
      DTC is not output B

      HINT: 

      Reinstall the sensor, connectors, etc. and restore the vehicle to its prior condition before rechecking DTCs.

    Result: 

    B 

    END 

    Result: 

    A 

    See step  11

  11. REPLACE BRAKE ACTUATOR ASSEMBLY 
    1. Replace the skid control ECU (brake actuator assembly).

      Refer to COMPONENTS [09/2015 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  12

  12. RECONFIRM DTC 
    1. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Clear DTCs 

    2. Start the engine.
    3. Drive the vehicle at a speed of 30 km/h (19 mph) or more and check that the same DTC is output.

      Refer to DTC CHECK / CLEAR [09/2015 - 08/2019]

      Chassis > Four Wheel Drive > Trouble Codes 

      Result

      Result Proceed to
      DTC is not output A
      DTC is output B

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE 4WD ECU ASSEMBLY. Refer to  COMPONENTS [09/2015 - ] 

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