DIFFERENTIAL SYSTEM(w/ Differential Lock) SYSTEM DESCRIPTION


  1. DESCRIPTION


    • The differential system (w/ Differential Lock) directly connects the rear left and right wheels so that even if one wheel slips while driving where drive torque transmission is difficult (such as on sand), the drive torque of the other wheel is ensured and traction is provided in emergencies.

    • except Pre-Runner:

      When the transfer is in L4 and the differential lock switch is operated, the 4 wheel drive control ECU supplies power to the solenoid to switch the rear differential from free to locked, and cuts power to switch the rear differential from locked to free.

      for Pre-Runner:

      When the differential lock switch is operated, the 4 wheel drive control ECU supplies power to the solenoid to switch the rear differential from free to locked, and cuts power to switch the rear differential from locked to free.

  2. INDICATOR LIGHT AND BUZZER OPERATING CONDITIONS


    1. except Pre-Runner:

      Mode 2WD/4WD Mode Status Rear Differential Lock Indicator Light 4WD Indicator Light (Green) and 4LO Indicator Light Buzzer
      Rear differential free H2 or H4 Not illuminated Turned off or illuminated to display H2 or H4 mode status Not sounding
      Rear differential free L4 Not illuminated Illuminated Not sounding
      Rear differential switching between free and locked L4 Blinking Illuminated Not sounding
      Rear differential locked L4 Illuminated Illuminated Not sounding
      Rear differential lock malfunction H2, H4 or L4 Rapidly blinking Illuminated Not sounding

      • Blinking: Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)

      • Rapidly blinking: Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)

    2. for Pre-Runner:

      Mode Rear Differential Lock Indicator Light Buzzer
      Rear differential free Not illuminated Not sounding
      Rear differential switching between free and locked Blinking Not sounding
      Rear differential locked Illuminated Not sounding
      Rear differential lock malfunction Rapidly blinking Not sounding

      • Blinking: Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)

      • Rapidly blinking: Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)

  3. FUNCTION OF COMPONENTS

    Components Functions
    Differential lock coil Switches the rear differential between free and locked according to commands from the 4 wheel drive control ECU.
    Rear differential lock position switch (No. 1 transfer indicator switch) Detects the rear differential locked condition and sends that information to the 4 wheel drive control ECU.
    Combination meter assembly

    • Rear differential lock indicator light

    • Buzzer

    Illuminates to inform the user of the locked condition.

    Blinks to inform the user of switching between free and locked.

    Rapidly blinks to inform the user of a system malfunction.

    except Pre-Runner:

    When the differential lock switch is pressed while not in L4, the indicator light blinks 3 times and the buzzer sounds 3 times.

    Tech Tips

    When the rear differential is in the locked condition, ABS, VSC and TRC are prohibited.
    Differential lock switch Selects free or locked for the rear differential.
    Skid control ECU (brake actuator assembly) Outputs wheel speed signals to the 4 wheel drive control ECU via CAN communication.
    4 wheel drive control ECU Detects the vehicle status according to signals such as the wheel and vehicle speed signals received via CAN communication, and operates or stops the differential lock coil and switches the rear differential between locked and free according to the differential lock switch signal.

    • Blinking: Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)

    • Rapidly blinking: Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)