DYNAMIC TORQUE CONTROL AWD SYSTEM, Diagnostic DTC:C1337/91

DTC Code DTC Name
C1337/91 Diameter of the Tire is not Uniform

DESCRIPTION

The 4WD ECU assembly outputs this DTC if a difference in tire size is detected.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1337/91 Diameter of the Tire is not Uniform

When the following continues for 36 seconds or more:

At a vehicle speed of 30 km/h (18.6 mph) or more, the average speed difference between the front wheel and rear wheel is 4% or more.

  • Tire size or pressure (front and rear tires)

  • Speed sensor circuit

  • Front speed sensor

  • Rear speed sensor

  • Front skid control sensor wire (w/ AVS)

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

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

  • Wire harness and connector

  • Skid control ECU (Brake actuator assembly)

  • 4WD ECU assembly

WIRING DIAGRAM

B0058CKE02
B005BHXE03
*a Rear Speed Sensor RH
*b Rear Speed Sensor LH
*c Skid Control ECU (Brake Actuator Assembly)

CAUTION / NOTICE / HINT

Note

When the 4WD ECU assembly is replaced with a normal one from another vehicle, it is necessary to perform calibration.

Click here

Tech Tips

Check the condition of each related circuit connector before troubleshooting.

Click here

PROCEDURE


  1. CHECK TIRE CONDITION


    1. Check the size and condition of all 4 tires.

      Tech Tips

      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

    NG

    REPLACE PERFORM AIR PRESSURE ADJUSTMENT OR REPLACE TIRES SO THAT ALL 4 TIRES ARE SAME IN SIZE Click here

    OK

  2. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      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.

      Click here


      Chassis > Four Wheel Drive > Trouble Codes

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

      Click here


      Chassis > ABS/VSC/TRC > Trouble Codes

    5. Read the DTCs using the GTS.

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

    B

    INSPECT FRONT SKID CONTROL SENSOR WIRE Click here

    C

    CHECK FOR INTERMITTENT PROBLEMS Click here

    D

    REPAIR CIRCUIT INDICATED BY OUTPUT CODE (BRAKE CONTROL SYSTEM) Click here

    A

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


    1. Turn the engine switch off.

    2. Disconnect the A36 skid control ECU (brake actuator assembly) connector.

    3. Disconnect the A12, A13, P14 and/or Q8 speed sensor 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
      A36-31 (FR+) - A12-6 (FR+) Always Below 1 Ω
      A36-30 (FR-) - A12-5 (FR-) Always
      A36-31 (FR+) or A12-6 (FR+) - Body ground and other terminals Always 10 kΩ or higher
      A36-30 (FR-) or A12-5 (FR-) - Body ground and other terminals Always
      for Front LH:
      Tester Connection Condition Specified Condition
      A36-18 (FL+) - A13-6 (FL+) Always Below 1 Ω
      A36-17 (FL-) - A13-5 (FL-) Always
      A36-18 (FL+) or A13-6 (FL+) - Body ground and other terminals Always 10 kΩ or higher
      A36-17 (FL-) or A13-5 (FL-) - Body ground and other terminals Always
      for Rear RH:
      Tester Connection Condition Specified Condition
      A36-16 (RR+) - P14-1 (RR+) Always Below 1 Ω
      A36-15 (RR-) - P14-2 (RR-) Always
      A36-16 (RR+) or P14-1 (RR+) - Body ground and other terminals Always 10 kΩ or higher
      A36-15 (RR-) or P14-2 (RR-) - Body ground and other terminals Always
      for Rear LH:
      Tester Connection Condition Specified Condition
      A36-29 (RL+) - Q8-1 (RL+) Always Below 1 Ω
      A36-28 (RL-) - Q8-2 (RL-) Always
      A36-29 (RL+) or Q8-1 (RL+) - Body ground and other terminals Always 10 kΩ or higher
      A36-28 (RL-) or Q8-2 (RL-) - Body ground and other terminals Always
      Result
      Proceed to
      OK
      NG

    OK

    GO TO STEP 6 Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. INSPECT FRONT 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 A50 and/or A51 front skid control sensor wire connector(s).

    4. Disconnect the A and/or B front skid control sensor wire connector(s).

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

      B005A9FC11
      *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 RH:
      Tester Connection Condition Specified Condition
      A-1 - A50-6 (FR+) Always Below 1 Ω
      A-2 - A50-5 (FR-) Always
      A-1 or A50-6 (FR+) - Body ground and other terminals Always 10 kΩ or higher
      A-2 or A50-5 (FR-) - Body ground and other terminals Always
      for LH:
      Tester Connection Condition SpecifiedCondition
      B-1 - A51-6 (FL+) Always Below 1 Ω
      B-2 - A51-5 (FL-) Always
      B-1 or A51-6 (FL+) - Body ground and other terminals Always 10 kΩ or higher
      B-2 or A51-5 (FL-) - Body ground and other terminals Always
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FRONT SKID CONTROL SENSOR WIRE

    OK

  5. 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. Reconnect the A50 and/or A51 front skid control sensor wire connector(s).

    3. Disconnect the A36 skid control ECU (brake actuator assembly) connector.

    4. Disconnect the P14 and/or Q8 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
      A36-31 (FR+) - A-1 Always Below 1 Ω
      A36-30 (FR-) - A-2 Always
      A36-31 (FR+) or A-1 - Body ground and other terminals Always 10 kΩ or higher
      A36-30 (FR-) or A-2 - Body ground and other terminals Always
      for Front LH:
      Tester Connection Condition Specified Condition
      A36-18 (FL+) - B-1 Always Below 1 Ω
      A36-17 (FL-) - B-2 Always
      A36-18 (FL+) or B-1 - Body ground and other terminals Always 10 kΩ or higher
      A36-17 (FL-) or B-2 - Body ground and other terminals Always
      for Rear RH:
      Tester Connection Condition Specified Condition
      A36-16(RR+) - P14-1(RR+) Always Below 1 Ω
      A36-15 (RR-) - P14-2 (RR-) Always
      A36-16 (RR+) or P14-1 (RR+) - Body ground and other terminals Always 10 kΩ or higher
      A36-15 (RR-) or P14-2 (RR-) - Body ground and other terminals Always
      for Rear LH:
      Tester Connection Condition Specified Condition
      A36-29 (RL+) - Q8-1 (RL+) Always Below 1 Ω
      A36-28 (RL-) - Q8-2 (RL-) Always
      A36-29 (RL+) or Q8-1 (RL+) - Body ground and other terminals Always 10 kΩ or higher
      A36-28 (RL-) or Q8-2 (RL-) - Body ground and other terminals Always
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. PERFORM TEST MODE (SIGNAL CHECK)


    1. Turn the engine switch off.

    2. Perform the sensor check in the Test Mode procedure.

      Click here


      Chassis > ABS/VSC/TRC > Utility
      Tester Display
      Signal Check
      OK
      All Test Mode (signal check) inspection items are normal.
      Result
      Proceed to
      OK
      NG

    NG

    CHECK SPEED SENSOR ROTOR Click here

    OK

  7. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      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.

      Click here


      Chassis > Four Wheel Drive > Trouble Codes
      Result
      Proceed to
      DTC is output
      DTC is not output

    DTC is output

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    DTC is not output

    CHECK FOR INTERMITTENT PROBLEMS Click here

  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: Click here

      for Rear: Click here

    3. Check the speed sensor 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


      • If the front speed sensor rotor needs to be replaced, replace it together with the front axle hub sub-assembly.

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

      Result
      Proceed to
      OK
      NG

    NG

    CLEAN OR REPLACE SPEED SENSOR ROTOR

    OK

  9. REPLACE SPEED SENSOR


    1. Turn the engine switch off.

    2. Replace the front speed sensor or the rear speed sensor.

      for Front: Click here

      for Rear: Click here

      Note

      Check the speed sensor signal after replacement.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  10. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      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.

      Click here


      Chassis > Four Wheel Drive > Trouble Codes
      Result
      Proceed to
      DTC is output
      DTC is not output

      Tech Tips

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


    DTC is not output

    END

    DTC is output

  11. REPLACE BRAKE ACTUATOR ASSEMBLY


    1. Replace the skid control ECU (brake actuator assembly).

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  12. RECONFIRM DTC


    1. Clear the DTCs.

      Click here


      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.

      Click here


      Chassis > Four Wheel Drive > Trouble Codes
      Result
      Proceed to
      DTC is output
      DTC is not output

    DTC is output

    REPLACE 4WD ECU ASSEMBLY fro LHD: Click here
    REPLACE 4WD ECU ASSEMBLY for RHD: Click here

    DTC is not output

    END