4WD Control System / Transfer Case Control System: Inspection: Inspection

1. Start the engine.
2. Change the transfer position switch from the H2 to H4.
3. Check that the 4WD indicator light illuminates.

   OK

   4WD indicator light comes on or 4WD indicator light comes on after blinking.

   If the result is not as specified, inspect the transfer indicator switch (4WD position) and four wheel drive control ECU. 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 DIAGNOSIS SYSTEM . Then check the combination meter. Refer to PROBLEM SYMPTOMS TABLE .

1. Turn the ignition switch to ON.
2. Move the shift lever to N (vehicle is stopped).
3. Change the transfer position switch from H4 to L4.
4. Check the 4LO indicator light.

   OK

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

   If the result is not as specified, inspect the transfer indicator switch (L4 position) and four wheel drive control ECU. 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 DIAGNOSIS SYSTEM . Then check the combination meter. Refer to PROBLEM SYMPTOMS TABLE .

Fig 1: Identifying Four Wheel Drive Control ECU Connectors (Power Supply)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard voltage

If the result is not as specified, inspect the fuse, harness or connector. If the harness or connector is malfunctioning, repair or replace the harness or connector. If the harness or connector is normal, replace the four wheel drive control ECU. Refer to REMOVAL .

Standard resistance

If the result is not as specified, repair or replace the harness, fuse or connector.

Fig 2: Identifying Four Wheel Drive Control ECU Connectors (Transfer Indicator Switch)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard voltage

If the result is not as specified, check the power supply. If the power supply is normal, inspect the transfer indicator switch. Refer to REMOVAL .

Fig 3: Identifying Four Wheel Drive Control ECU - Transfer Indicator Switch Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the F47 four wheel drive control ECU connector.
2. Disconnect the B53 transfer indicator switch connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   F47-3 (4WD) - B53-2	Always	Below 1 Ω
   F47-3 (4WD) - Body ground	Always	100 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *a

   Front view of wire harness connector (to Four Wheel Drive Control ECU)

   *b

   Front view of wire harness connector (to Transfer Indicator Switch)

   If the result is not as specified, repair or replace the harness or connector.

Fig 4: Identifying Four Wheel Drive Control ECU - Transfer Indicator Switch Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Disconnect the F47 four wheel drive control ECU connector.
2. Disconnect the B54 transfer indicator switch connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance

   Tester Connection	Condition	Specified Condition
   F47-16 (4WDL) - B54-1	Always	Below 1 Ω
   F47-16 (4WDL) - Body ground	Always	100 kΩ or higher

   TEXT IN ILLUSTRATION
   
   

   *a

   Front view of wire harness connector (to Four Wheel Drive Control ECU)

   *b

   Front view of wire harness connector (to Transfer Indicator Switch)

   If the result is not as specified, repair or replace the harness or connector.

1. Disconnect the F46 and F47 four wheel drive control ECU connectors.
2. Disconnect the D1 A.D.D. actuator connector.
3. Measure the resistance according to the value(s) in the table below.
   Fig 5: Identifying Four Wheel Drive Control ECU Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance

   Tester Connection	Condition	Specified Condition
   F47-1 (DL1) - D1-6 (DL1)	Always	Below 1 Ω
   F47-1 (DL1) - Body ground	Always	100 kΩ or higher
   F47-2 (DL2) - D1-5 (DL2)	Always	Below 1 Ω
   F47-2 (DL2) - Body ground	Always	100 kΩ or higher
   F47-14 (ADD) - D1-3 (ADD)	Always	Below 1 Ω
   F47-14 (ADD) - Body ground	Always	100 kΩ or higher
   F46-2 (DM1) - D1-1 (DM1)	Always	Below 1 Ω
   F46-2 (DM1) - Body ground	Always	100 kΩ or higher
   F46-6 (DM2) - D1-2 (DM2)	Always	Below 1 Ω
   F46-6 (DM2) - Body ground	Always	100 kΩ or higher
   D1-4 (GND) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a

   Front view of wire harness connector (to Four Wheel Drive Control ECU)

   *b

   Front view of wire harness connector (to A.D.D. Actuator)

   If the result is not as specified, repair or replace the harness or connector. If the harness or connector is normal, check the ECU output voltage.

1. Connect the F46 and F47 four wheel drive control ECU connectors.
2. Connect the D1 A.D.D. actuator connector.
3. Measure the voltage according to the value(s) in the table below.
   Fig 6: Identifying Four Wheel Drive Control ECU Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   F46-2 (DM1) - F46-4 (GND)	Ignition switch ON Transfer position switch H2 → H4, L4 (A.D.D. actuator motor stopped)	Below 1.5 V
   	Ignition switch ON Transfer position switch H2 → H4, L4 (During operation of A.D.D. actuator motor from FREE to LOCK)	10 to 14 V
   F46-6 (DM2) - F46-4 (GND)	Ignition switch ON Transfer position switch H4, L4 → H2 (A.D.D. actuator motor stopped)	Below 1.5 V
   	Ignition switch ON Transfer position switch H4, L4 → H2 (During operation of A.D.D. actuator motor from LOCK to FREE)	10 to 14 V
   F47-1 (DL1) - F46-4 (GND)	Ignition switch ON Transfer position switch H2	Below 1.5 V
   	Ignition switch ON Transfer position switch H4 or L4	10 to 14 V
   F47-2 (DL2) - F46-4 (GND)	Ignition switch ON Transfer position switch H4 or L4	Below 1.5 V
   	Ignition switch ON Transfer position switch H2	10 to 14 V
   F47-14 (ADD) - F46-4 (GND)	Ignition switch ON Transfer position switch H4 or L4	Below 1.5 V
   	Ignition switch ON Transfer position switch H2	10 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Four Wheel Drive Control ECU)

   If the result is not as specified, determine if the malfunction is on the four wheel drive control ECU side or the actuator side by disconnecting the connector of the A.D.D. actuator, and then check the ECU output voltage.

1. Connect the F46 and F47 four wheel drive control ECU connectors.
2. Disconnect the D1 A.D.D. actuator connector.
3. Measure the voltage according to the value(s) in the table below.
   Fig 7: Identifying Four Wheel Drive A.D.D. Actuator Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   D1-3 (ADD) - D1-4 (GND)	Ignition switch ON	10 to 14 V
   D1-5 (DL2) - D1-4 (GND)	Ignition switch ON	10 to 14 V
   D1-6 (DL1) - D1-4 (GND)	Ignition switch ON	10 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to A.D.D. Actuator)

   If the result is not as specified, replace the four wheel drive control ECU. Refer to REMOVAL . If the voltage is normal, inspect the A.D.D. actuator, because the voltage applied to the motor cannot be measured.

1. Disconnect the B55 transfer shift actuator assembly connector.
2. Disconnect the F47 and F46 four wheel drive control ECU connectors.
3. Measure the resistance according to the value(s) in the table below.
   Fig 8: Identifying Four Wheel Drive Control ECU & Transfer Sift Actuator Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance

   Tester Connection	Condition	Specified Condition
   F47-6 (TL1) - B55-5 (TL1)	Always	Below 1 Ω
   F47-6 (TL1) - Body ground	Always	100 kΩ or higher
   F47-7 (TL2) - B55-6 (TL2)	Always	Below 1 Ω
   F47-7 (TL2) - Body ground	Always	100 kΩ or higher
   F47-8 (TL3) - B55-3 (TL3)	Always	Below 1 Ω
   F47-8 (TL3) - Body ground	Always	100 kΩ or higher
   F46-8 (TM1) - B55-2 (TM1)	Always	Below 1 Ω
   F46-8 (TM1) - Body ground	Always	100 kΩ or higher
   F46-7 (TM2) - B55-1 (TM2)	Always	Below 1 Ω
   F46-7 (TM2) - Body ground	Always	100 kΩ or higher
   B55-4 (GND1) - Body ground	Always	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

   *a

   Front view of wire harness connector (to Four Wheel Drive Control ECU)

   *b

   Front view of wire harness connector (to Transfer Shift Actuator Assembly)

   If the result is not as specified, repair or replace the harness or connector. If the harness or connector is normal, check the four wheel drive control ECU output voltage.

1. Connect the F47 and F46 four wheel drive control ECU connectors.
2. Connect the B55 transfer shift actuator assembly connectors.
3. Measure the voltage according to the value(s) in the table below.
   Fig 9: Identifying Four Wheel Drive Control ECU Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   F46-7 (TM2) - F46-4 (GND)	Ignition switch ON Transfer position switch L4 → H4 (During operation of transfer shift actuator motor from LOW to HIGH)	10 to 14 V
   	Ignition switch ON Transfer position switch L4 → H4 (Transfer shift actuator motor stopped)	Below 1.5 V
   F46-8 (TM1) - F46-4 (GND)	Ignition switch ON Transfer position switch H4 → L4 (During operation of transfer shift actuator motor from HIGH to LOW)	10 to 14 V
   	Ignition switch ON Transfer position switch H4 → L4 (Transfer shift actuator motor stopped)	Below 1.5 V
   F47-6 (TL1) - F46-4 (GND)	Ignition switch ON Transfer position switch H2	Below 1.5 V
   	Ignition switch ON Transfer position switch H4 or L4	10 to 14 V
   F47-7 (TL2) - F46-4 (GND)	Ignition switch ON Transfer position switch H4	Below 1.5 V
   	Ignition switch ON Transfer position switch H2 or L4	10 to 14 V
   F47-8 (TL3) - F46-4 (GND)	Ignition switch ON Transfer position switch L4	Below 1.5 V
   	Ignition switch ON Transfer position switch H2 or H4	10 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Component with harness connected (Four Wheel Drive Control ECU)

   If the result is not as specified, determine if a malfunction is on the four wheel drive control ECU side or transfer shift actuator assembly side by disconnecting the connector of the transfer shift actuator assembly, and then check the four wheel drive control ECU output voltage.

1. Disconnect the B55 transfer shift actuator assembly connector.
2. Connect the F47 and F46 four wheel drive control ECU connector.
3. Measure the voltage according to the value(s) in the table below.
   Fig 10: Identifying Four Wheel Drive Transfer Shift Actuator Assembly Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   B55-3 (TL3) - B55-4 (GND1)	Ignition switch ON	10 to 14 V
   B55-5 (TL1) - B55-4 (GND1)	Ignition switch ON	10 to 14 V
   B55-6 (TL2) - B55-4 (GND1)	Ignition switch ON	10 to 14 V

   TEXT IN ILLUSTRATION
   
   

   *a	Front view of wire harness connector (to Transfer Shift Actuator Assembly)

   If the result is not as specified, replace the four wheel drive control ECU. Refer to REMOVAL . If the voltage is normal, inspect the transfer shift actuator assembly, because the voltage applied to the motor cannot be measured.

1. Remove the transfer shift actuator assembly. Refer to DISASSEMBLY .
2. Check the H2 to H4 switch. Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the H2 to H4 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 performing the operation described above, use the stop LP relay.

   Fig 11: Identifying LP Relay & Transfer Shift Actuator Assembly Harness Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. After the H2 to H4 switch is complete, inspect the limit switch.

      Standard resistance

      Tester Connection	Condition	Specified Condition
      3 (TL3) - 4 (GND1)	After H2 to H4 switch is complete	100 kΩ or higher
      5 (TL1) - 4 (GND1)	After H2 to H4 switch is complete	Below 1 Ω
      6 (TL2) - 4 (GND1)	After H2 to H4 switch is complete	100 kΩ or higher

      TEXT IN ILLUSTRATION
      
      

      *1	Stop LP Relay	-	-
      *a	Component without harness connected (Transfer Shift Actuator Assembly)	*b	H2 to H4

      If the result is not as specified, replace the transfer shift actuator assembly. Refer to DISASSEMBLY . If the transfer shift actuator assembly is normal, replace the four wheel drive control ECU. Refer to REMOVAL .

3. Check the H4 to H2 switch. Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the H4 to H2 position.
   Fig 12: Connecting Lines Via Relay

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. After the H4 to H2 switch is complete, inspect the limit switch.

      Standard resistance

      Tester Connection	Condition	Specified Condition
      3 (TL3) - 4 (GND1)	After H4 to H2 switch is complete	100 kΩ or higher
      5 (TL1) - 4 (GND1)	After H4 to H2 switch is complete	Below 1 Ω
      6 (TL2) - 4 (GND1)	After H4 to H2 switch is complete	100 kΩ or higher

      TEXT IN ILLUSTRATION
      
      

      *1	Stop LP Relay	-	-
      *a	Component without harness connected (Transfer Shift Actuator Assembly)	*b	H4 to H2

      If the result is not as specified, replace the transfer shift actuator assembly. Refer to DISASSEMBLY . If the transfer shift actuator assembly is normal, replace the four wheel drive control ECU. Refer to REMOVAL .

4. Check the H4 to L4 switch. Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the H4 to L4 position.
   Fig 13: Connecting Lines Via Relay

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. After the H4 to L4 switch is complete, inspect the limit switch.

      Standard resistance

      Tester Connection	Condition	Specified Condition
      3 (TL3) - 4 (GND1)	After H4 to H2 switch is complete	Below 1 Ω
      5 (TL1) - 4 (GND1)	After H4 to H2 switch is complete	100 kΩ or higher
      6 (TL2) - 4 (GND1)	After H4 to H2 switch is complete	100 kΩ or higher

      TEXT IN ILLUSTRATION
      
      

      *1	Stop LP Relay	-	-
      *a	Component without harness connected (Transfer Shift Actuator Assembly)	*b	H4 to L4

      If the result is not as specified, replace the transfer shift actuator assembly. Refer to DISASSEMBLY . If the transfer shift actuator assembly is normal, replace the four wheel drive control ECU. Refer to REMOVAL .

5. Check the L4 to H4 switch. Connect lines via a relay as shown in the illustration, then check that the actuator fork moves from the H4 to L4 position.
   Fig 14: Connecting Lines Via Relay

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. After the L4 to H4 switch is complete, inspect the limit switch.

      Standard resistance

      Tester Connection	Condition	Specified Condition
      3 (TL3) - 4 (GND1)	After H4 to H2 switch is complete	100 kΩ or higher
      5 (TL1) - 4 (GND1)	After H4 to H2 switch is complete	100 kΩ or higher
      6 (TL2) - 4 (GND1)	After H4 to H2 switch is complete	Below 1 Ω

      TEXT IN ILLUSTRATION
      
      

      *1	Stop LP Relay	-	-
      *a	Component without harness connected (Transfer Shift Actuator Assembly)	*b	L4 to H4

      If the result is not as specified, replace the transfer shift actuator assembly. Refer to DISASSEMBLY . If the transfer shift actuator assembly is normal, replace the four wheel drive control ECU. Refer to REMOVAL .