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Inspection [08/2015 - 08/2017]: Procedure

  1. INSPECT INDICATOR LIGHT 
    1. 4HI Indicator Light:
      1. Turn the ignition switch to ON.
      2. Change the 4WD control switch from 2WD to 4H. Then move the shift lever to N (vehicle is stopped).
      3. Check the 4HI indicator light.
        GTY234824Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK

        4HI indicator light comes on or 4HI indicator light comes on after blinking

        HINT: 

        If there is a malfunction, inspect the switch, ECU, transfer shift actuator and A.D.D. actuator. If the system is normal, there may be a malfunction in the CAN communication system or combination meter. In this case, first check the CAN communication system (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2017] ). Then check the combination meter (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] ).

    2. 4LO Indicator Light:
      1. Turn the ignition switch to ON.
      2. Change the 4WD control switch from 2WD to 4H. Then move the shift lever to N (vehicle is stopped) after the 4HI indicator light illuminates.
      3. Change the 4WD control switch from 4H to 4L.
      4. Check the 4LO indicator light.
        GTY244122Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK

        4LO indicator light comes on or 4LO indicator light comes on after blinking

        HINT: 

        If there is a malfunction, inspect the switch, ECU, transfer shift actuator and A.D.D. actuator. If the system is normal, there may be a malfunction in the CAN communication system or combination meter. In this case, first check the CAN communication system (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2017] ). Then check the combination meter (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] ).

    3. CENTER DIFF. Indicator Light:
      1. Turn the ignition switch to ON.
      2. Change the 4WD control switch from 2WD to 4H. Then move the shift lever to N (vehicle is stopped). (4HI indicator light illuminates).
      3. Press the center differential lock switch.
      4. Check the CENTER DIFF. indicator light.
        GTY594359Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        OK

        CENTER DIFF. indicator light comes on or CENTER DIFF. indicator light comes on after it is blinking

        HINT: 

        If there is a malfunction, inspect the switches, ECU, transfer, and shift actuator. If the system is normal, there may be a malfunction in the CAN communication system or combination meter. In this case, first check the CAN communication system (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2017] ). Then check the combination meter (Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - ] ).

  2. INSPECT FUSE (4WD) 
    1. Remove the 4WD fuse from the main body ECU.
      GTY590346Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      4WD fuse Always Below 1 Ω

      HINT: 

      If a fuse is blown, inspect the harness connected to the fuse for a short circuit, and repair or replace the harness and replace the fuse.

  3. INSPECT 4WD CONTROL ECU (POWER SUPPLY) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY555442Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A29-3 (IG) - Body ground Ignition switch ON 11 to 14 V

      HINT: 

      If there is a malfunction, inspect the harness or connector. If the harness is malfunctioning, repair or replace harness or connector. If the harness or connector is normal, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ).

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A29-4 (GND) - Body ground Always Below 1 Ω

      HINT: 

      If there is a malfunction, repair or replace the harness or connector.

  4. INSPECT 4WD CONTROL ECU (4WD CONTROL SWITCH) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY578176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A28-11 (2-4) - Body ground Ignition switch ON
      4WD control switch 2WD      		 Below 1.5 V
      Ignition switch ON
      4WD control switch 4H      		 Below 1.5 V
      Ignition switch ON
      4WD control switch 4L      		 10.5 to 14 V
      A28-13 (LO) - Body ground Ignition switch ON
      4WD control switch 2WD      		 10.5 to 14 V
      Ignition switch ON
      4WD control switch 4H      		 Below 1.5 V
      Ignition switch ON
      4WD control switch 4L      		 Below 1.5 V

      HINT: 

      If there is a malfunction, check the power supply. If the power supply is normal, inspect the 4WD control switch (Refer to ON-VEHICLE INSPECTION [08/2015 - 08/2017] ).

  5. INSPECT 4WD CONTROL ECU (CENTER DIFFERENTIAL LOCK SWITCH) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY605257Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A28-12 (DL) - Body ground Ignition switch ON
      Center differential lock switch ON      		 Below 1.5 V
      Ignition switch ON
      Center differential lock switch OFF      		 10.5 to 14 V

      HINT: 

      If there is a malfunction, check the power supply. If the power supply is normal, inspect the center differential lock switch (Refer to INSPECTION [08/2015 - ] ).

  6. INSPECT MULTI MODE TRANSFER SHIFT ACTUATOR 

    HINT: 

    After inspecting the power supply, 4WD control switch and center differential lock switch, inspect the multi mode transfer shift actuator.

    1. Check the harness and connector (ECU - multi mode transfer shift actuator).
      1. Disconnect the D45 actuator connector.
      2. Disconnect the A28 and A29 ECU connectors.
      3. Measure the resistance according to the value(s) in the table below.
        GTY540777Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Resistance

        Tester Connection Condition Specified Condition
        A28-6 (TL1) - D45-4 (TL1) Always Below 1 Ω
        A28-6 (TL1) - Body ground Always 10 kΩ or higher
        A28-7 (TL2) - D45-6 (TL2) Always Below 1 Ω
        A28-7 (TL2) - Body ground Always 10 kΩ or higher
        A28-8 (TL3) - D45-5 (TL3) Always Below 1 Ω
        A28-8 (TL3) - Body ground Always 10 kΩ or higher
        A28-14 (4WD) - D45-3 (CDL) Always Below 1 Ω
        A28-14 (4WD) - Body ground Always 10 kΩ or higher
        A29-7 (TM2) - D45-2 (TM2) Always Below 1 Ω
        A29-7 (TM2) - Body ground Always 10 kΩ or higher
        A29-8 (TM1) - D45-1 (TM1) Always Below 1 Ω
        A29-8 (TM1) - Body ground Always 10 kΩ or higher
        D45-7 (GND1) - Body ground Always Below 1 Ω

        HINT: 

        If there is a malfunction, repair or replace harness or connector. If the harness or connector is normal, check the ECU output voltage.

    2. Check the 4WD control ECU (multi mode transfer shift actuator).
      1. Connect the A28 and A29 ECU connectors.
      2. Connect the D45 actuator connector.
      3. Measure the voltage according to the value(s) in the table below.
        GTY610224Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        A29-8 (TM1) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD → 4H or 4L (During operation of Multi mode transfer shift actuator motor from 2WD to 4WD HIGH or 4WD LOW)        		 10 to 14 V
        Ignition switch ON
        4WD control switch 2WD → 4H or 4L (Multi mode transfer shift actuator motor stopped)        		 Below 1.5 V
        A29-7 (TM2) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H or 4L → 2WD (During operation of Multi mode transfer shift actuator motor from 4WD HIGH or 4WD LOW to 2WD)        		 10 to 14 V
        Ignition switch ON
        4WD control switch 4H or 4L → 2WD (Multi mode transfer shift actuator motor stopped)        		 Below 1.5 V
        A28-6 (TL1) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD        		 Below 1.5 V
        Ignition switch ON
        4WD control switch 4H or 4L        		 10.5 to 14 V
        A28-7 (TL2) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD        		 10.5 to 14 V
        Ignition switch ON
        4WD control switch 4H or 4L
        Center differential Lock        		 10.5 to 14 V
        Ignition switch ON
        4WD control switch 4H or 4L
        Center differential Free        		 Below 1.5 V
        A28-8 (TL3) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD        		 10.5 to 14 V
        Ignition switch ON
        4WD control switch 4H or 4L
        Center differential Lock        		 Below 1.5 V
        Ignition switch ON
        4WD control switch 4H or 4L
        Center differential Free        		 10.5 to 14 V
        A28-14 (4WD) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD        		 9.5 to 14 V
        Ignition switch ON
        4WD control switch 4H or 4L
        Center differential Lock        		 Below 1.5 V
        Ignition switch ON
        4WD control switch 4H or 4L
        Center differential Free        		 9.5 to 14 V

        HINT: 

        If there is a malfunction, determine if the malfunction is on the ECU side or the actuator side by disconnecting the connector of the multi mode transfer shift actuator, and then checking the ECU output voltage.

    3. Check the 4WD control ECU.
      1. Disconnect the D45 actuator connector.
      2. Connect the A28 and A29 ECU connectors.
      3. Measure the voltage according to the value(s) in the table below.
        GTY558830Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        D45-3 (CDL) - D45-7 (GND1) Ignition switch ON 9.5 to 14 V
        D45-4 (TL1) - D45-7 (GND1) Ignition switch ON 10.5 to 14 V
        D45-6 (TL2) - D45-7 (GND1) Ignition switch ON 10.5 to 14 V
        D45-5 (TL3) - D45-7 (GND1) Ignition switch ON 10.5 to 14 V

        HINT: 

        If there is a malfunction, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ). If the voltage is normal, inspect the multi mode transfer shift actuator, because the voltage applied to the motor cannot be measured.

    4. Inspect the multi mode transfer shift actuator.
      1. Remove the transfer shift actuator (Refer to DISASSEMBLY [08/2015 - ] ).
      2. Check the 2WD to 4WD HIGH (H4L) switch.

        Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the 2WD to 4WD HIGH (H4L) position.

        NOTE:
        • Make sure to perform this inspection with the actuator removed from the vehicle. If this inspection is performed with the actuator installed to the vehicle, the actuator will be damaged.
        • When inspecting the actuator, make sure to operate it with the lines connected via a relay. If the lines are not connected via a relay and battery voltage is directly applied to the actuator, the actuator will be damaged.

        HINT: 

        When inspecting the operation described above, use the stop light control relay (BRK NO. 1).

        GTY568685Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. After the 2WD to 4WD HIGH (H4F) switch is complete, inspect the 4WD detection switch and limit switch.

          Standard Resistance

          Tester Connection Condition Specified Condition
          3 (CDL) - 7 (GND1) After 2WD to 4WD HIGH (H4F) switch is complete 100 kΩ or higher
          4 (TL1) - 7 (GND1) After 2WD to 4WD HIGH (H4F) switch is complete 100 kΩ or higher
          5 (TL3) - 7 (GND1) After 2WD to 4WD HIGH (H4F) switch is complete 100 kΩ or higher
          6 (TL2) - 7 (GND1) After 2WD to 4WD HIGH (H4F) switch is complete Below 1 Ω
      3. Check the 4WD HIGH (H4F) to 2WD switch.

        Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the 4WD HIGH (H4F) to 2WD position.

        GTY590681Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. After the 4WD HIGH (H4F) to 2WD switch is complete, inspect the 4WD detection switch and limit switch.

          Standard Resistance

          Tester Connection Condition Specified Condition
          3 (CDL) - 7 (GND1) After 4WD HIGH (H4F) to 2WD switch is complete 100 kΩ or higher
          4 (TL1) - 7 (GND1) After 4WD HIGH (H4F) to 2WD switch is complete Below 1 Ω
          5 (TL3) - 7 (GND1) After 4WD HIGH (H4F) to 2WD switch is complete 100 kΩ or higher
          6 (TL2) - 7 (GND1) After 4WD HIGH (H4F) to 2WD switch is complete 100 kΩ or higher

          HINT: 

          If there is a malfunction, replace the transfer shift actuator (Refer to DISASSEMBLY [08/2015 - ] ). If the transfer shift actuator is normal, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ).

  7. INSPECT A.D.D. ACTUATOR 

    HINT: 

    After inspecting the multi mode transfer shift actuator, inspect the A.D.D. actuator.

    1. Check the harness and connector (ECU - A.D.D. actuator).
      1. Disconnect the A28 and A29 ECU connectors.
      2. Disconnect the F1 actuator connector.
      3. Measure the resistance according to the value(s) in the table below.
        GTY580521Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Resistance

        Tester Connection Condition Specified Condition
        A28-9 (DL1) - F1-6 (DL1) Always Below 1 Ω
        A28-9 (DL1) - Body ground Always 100 kΩ or higher
        A28-10 (DL2) - F1-5 (DL2) Always Below 1 Ω
        A28-10 (DL2) - Body ground Always 100 kΩ or higher
        A28-15 (ADD) - F1-3 (ADD) Always Below 1 Ω
        A28-15 (ADD) - Body ground Always 100 kΩ or higher
        A29-1 (DM1) - F1-1 (DM1) Always Below 1 Ω
        A29-1 (DM1) - Body ground Always 100 kΩ or higher
        A29-5 (DM2) - F1-2 (DM2) Always Below 1 Ω
        A29-5 (DM2) - Body ground Always 100 kΩ or higher
        F1-4 (GND) - Body ground Always Below 1 Ω

        HINT: 

        If there is a malfunction, repair or replace harness or connector. If the harness or connector is normal, check the ECU output voltage.

    2. Check the 4WD control ECU (A.D.D. actuator).
      1. Connect the A28 and A29 ECU connectors.
      2. Connect the F1 actuator connector.
      3. Measure the voltage according to the value(s) in the table below.
        GTY552294Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        A29-1 (DM1) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H (During operation of A.D.D. actuator from Lock to Free)        		 10 to 14 V
        Ignition switch ON
        4WD control switch 4H (A.D.D. actuator Free)        		 Below 1.5 V
        A29-5 (DM2) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H (during operation of A.D.D. actuator from Free to Lock)        		 10 to 14 V
        Ignition switch ON
        4WD control switch 4H (A.D.D. actuator Lock)        		 Below 1.5 V
        A28-9 (DL1) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD (A.D.D. actuator Free)        		 10.5 to 14 V
        Ignition switch ON
        4WD control switch 4H (A.D.D. actuator Lock)        		 Below 1.5 V
        A28-10 (DL2) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD (A.D.D. actuator Free)        		 Below 1.5 V
        Ignition switch ON
        4WD control switch 4H (A.D.D. actuator Lock)        		 10.5 to 14 V
        A28-15 (ADD) - A29-4 (GND) Ignition switch ON
        4WD control switch 2WD        		 10 to 14 V
        Ignition switch ON
        4WD control switch 4H or 4L        		 Below 1.5 V

        HINT: 

        If there is a malfunction, determine if the malfunction is on the ECU side or the actuator side by disconnecting the connector of the A.D.D. actuator, and then checking the ECU output voltage.

    3. Check the 4WD control ECU.
      1. Connect the A28 and A29 ECU connectors.
      2. Disconnect the F1 actuator connector.
      3. Measure the voltage according to the value(s) in the table below.
        GTY217843Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        F1-3 (ADD) - F1-4 (GND) Ignition switch ON 10 to 14 V
        F1-5 (DL2) - F1-4 (GND) Ignition switch ON 10.5 to 14 V
        F1-6 (DL1) - F1-4 (GND) Ignition switch ON 10.5 to 14 V

        HINT: 

        If there is a malfunction, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ). If the voltage is normal, inspect the A.D.D. actuator, because the voltage applied to the motor cannot be measured.

    4. Inspect the A.D.D. actuator.
      1. Remove the A.D.D. actuator (Refer to REMOVAL [08/2015 - ] ).
      2. Check the Free to Lock switch.

        Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the Free to the Lock position.

        NOTE:
        • Make sure to perform this inspection with the actuator removed from the vehicle. If this inspection is performed with the actuator installed to the vehicle, the actuator will be damaged.
        • When inspecting the actuator, operate it with the lines connected via a relay. If the lines are not connected via a relay and battery voltage is directly applied to the actuator, the actuator will be damaged.

        HINT: 

        When inspecting the operation described above, use the stop light control relay (BRK NO. 1).

        GTY558921Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. After the Free to Lock switch is complete, inspect the A.D.D. detection switch and limit switch.

          Standard Resistance

          Tester Connection Condition Specified Condition
          3 (ADD) - 4 (GND) After Free to Lock switch is complete Below 1 Ω
          5 (DL2) - 4 (GND) After Free to Lock switch is complete 100 kΩ or higher
          6 (DL1) - 4 (GND) After Free to Lock switch is complete Below 1 Ω
      3. Check the Lock to Free switch.

        Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the Lock to the Free position.

        GTY581004Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. After the Lock to Free switch is complete, inspect the A.D.D. detection switch and limit switch.

          Standard Resistance

          Tester Connection Condition Specified Condition
          3 (ADD) - 4 (GND) After Lock to Free switch is complete 100 kΩ or higher
          5 (DL2) - 4 (GND) After Lock to Free switch is complete Below 1 Ω
          6 (DL1) - 4 (GND) After Lock to Free switch is complete 100 kΩ or higher

          If there is a malfunction, replace the A.D.D. actuator (Refer to REMOVAL [08/2015 - ] ). If the A.D.D. actuator is normal, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ).

  8. INSPECT HIGH-LOW TRANSFER SHIFT ACTUATOR 

    HINT: 

    Before the inspection, check that the system is switched from 2WD to 4WD normally.

    1. Check the harness and connector (ECU - high-low transfer shift actuator).
      1. Disconnect the D46 high-low transfer shift actuator connector.
      2. Disconnect the A28 and A29 ECU connector.
      3. Measure the resistance according to the value(s) in the table below.
        GTY558011Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Resistance

        Tester Connection Condition Specified Condition
        A28-1 (HL1) - D46-4 (HL1) Always Below 1 Ω
        A28-1 (HL1) - Body ground Always 100 kΩ or higher
        A28-2 (HL2) - D46-6 (HL2) Always Below 1 Ω
        A28-2 (HL2) - Body ground Always 100 kΩ or higher
        A28-3 (HL3) - D46-5 (HL3) Always Below 1 Ω
        A28-3 (HL3) - Body ground Always 100 kΩ or higher
        A28-16 (NP) - D46-3 (N) Always Below 1 Ω
        A28-16 (NP) - Body ground Always 100 kΩ or higher
        A29-2 (HM1) - D46-1 (HM1) Always Below 1 Ω
        A29-2 (HM1) - Body ground Always 100 kΩ or higher
        A29-6 (HM2) - D46-2 (HM2) Always Below 1 Ω
        A29-6 (HM2) - Body ground Always 100 kΩ or higher
        D46-7 (GND) - Body ground Always Below 1 Ω

        If there is a malfunction, repair or replace the harness or connector. If the harness or connector is normal, check the ECU output voltage.

    2. Check the 4WD control ECU (high-low transfer shift actuator).
      1. Connect the A28 and A29 ECU connectors.
      2. Connect the D46 actuator connector.
      3. Measure the voltage according to the value(s) in the table below.
        GTY587243Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        A29-6 (HM2) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H → 4L (During operation of high-low transfer shift actuator motor from 4WD HIGH to 4WD LOW)        		 10 to 14 V
        Ignition switch ON
        4WD control switch 4H → 4L (High-low transfer shift actuator motor stopped)        		 Below 1.5 V
        A29-2 (HM1) - A29-4 (GND) Ignition switch ON
        4WD control switch 4L → 4H (During operation of high-low transfer shift actuator motor from 4WD LOW to 4WD HIGH)        		 10 to 14 V
        Ignition switch ON
        4WD control switch 4L → 4H (High-low transfer shift actuator motor stopped)        		 Below 1.5 V
        A28-1 (HL1) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H        		 Below 1.5 V
        Ignition switch ON
        4WD control switch 4L        		 10.5 to 14 V
        A28-2 (HL2) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H        		 10.5 to 14 V
        Ignition switch ON
        4WD control switch 4L        		 Below 1.5 V
        A28-3 (HL3) - A29-4 (GND) Ignition switch ON
        4WD control switch 4H        		 10.5 to 14 V
        Ignition switch ON
        1.5 seconds or less after 4WD HIGH to 4WD LOW switching operation        		 Below 1.5 V
        Ignition switch ON
        Over 1.5 seconds after 4WD HIGH to 4WD LOW switching operation        		 10.5 to 14 V
        A28-16 (NP) - A29-4 (GND) Ignition switch ON
        1.5 seconds or less after 4WD HIGH to 4WD LOW switching operation        		 Below 1.5 V
        Ignition switch ON
        Over 1.5 seconds after 4WD HIGH to 4WD LOW switching operation        		 10 to 14 V

        HINT: 

        If there is a malfunction, determine if the malfunction is on the ECU side or the actuator side by disconnecting the connector of the high-low transfer shift actuator, and then checking the ECU output voltage.

    3. Check the 4WD control ECU.
      1. Connect the A28 and A29 ECU connectors.
      2. Disconnect the D46 actuator connector.
      3. Measure the voltage according to the value(s) in the table below.
        GTY576464Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

        Standard Voltage

        Tester Connection Switch Condition Specified Condition
        D46-3 (N) - D46-7 (GND) Ignition switch ON 10 to 14 V
        D46-4 (HL1) - D46-7 (GND) Ignition switch ON 10.5 to 14 V
        D46-5 (HL3) - D46-7 (GND) Ignition switch ON 10.5 to 14 V
        D46-6 (HL2) - D46-7 (GND) Ignition switch ON 10.5 to 14 V

        HINT: 

        If there is a malfunction, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ). If the voltage is normal, inspect the high-low transfer shift actuator, because the voltage applied to the motor cannot be measured.

    4. Inspect the high-low transfer shift actuator.
      1. Remove the transfer shift actuator (Refer to DISASSEMBLY [08/2015 - ] ).
      2. Check the 4WD HIGH to 4WD LOW switch.

        Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the 4WD HIGH to 4WD LOW position.

        NOTE:
        • Perform this inspection with the actuator removed from the vehicle. If this inspection is performed with the actuator installed to the vehicle, the actuator will be damaged.
        • When inspecting the actuator, operate it with the lines connected via a relay. If the lines are not connected via a relay and battery voltage is directly applied to the actuator, the actuator will be damaged.

        HINT: 

        When inspecting the operation described above, use the stop light control relay (BRK NO. 1).

        GTY564395Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. After the 4WD HIGH to 4WD LOW switch is complete, inspect the neutral position detection switch and limit switch.

          Standard Resistance

          Tester Connection Condition Specified Condition
          3 (N) - 7 (GND) After 4WD HIGH to 4WD LOW switch is complete 100 kΩ or higher
          4 (HL1) - 7 (GND) After 4WD HIGH to 4WD LOW switch is complete 100 kΩ or higher
          5 (HL3) - 7 (GND) After 4WD HIGH to 4WD LOW switch is complete 100 kΩ or higher
          6 (HL2) - 7 (GND) After 4WD HIGH to 4WD LOW switch is complete Below 1 Ω
      3. Check the 4WD LOW to 4WD HIGH switch.

        Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the 4WD LOW to 4WD HIGH position.

        GTY555952Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        1. After the 4WD LOW to 4WD HIGH switch is complete, inspect the neutral position detection switch and limit switch.

          Standard Resistance

          Tester Connection Condition Specified Condition
          3 (N) - 7 (GND) After 4WD LOW to 4WD HIGH switch is complete 100 kΩ or higher
          4 (HL1) - 7 (GND) After 4WD LOW to 4WD HIGH switch is complete Below 1 Ω
          5 (HL3) - 7 (GND) After 4WD LOW to 4WD HIGH switch is complete 100 kΩ or higher
          6 (HL2) - 7 (GND) After 4WD LOW to 4WD HIGH switch is complete 100 kΩ or higher

          HINT: 

          If there is a malfunction, replace the transfer shift actuator (Refer to DISASSEMBLY [08/2015 - ] ). If the transfer shift actuator is normal, replace the 4WD control ECU (Refer to REMOVAL [08/2015 - ] ).

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