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Transfer System





VF4BM TRANSFER / 4WD / AWD: TRANSFER SYSTEM: INSPECTION

1. INSPECT INDICATOR LIGHT

(a) 4LO Indicator Light:

(1) Turn the engine switch On (IG).

(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.

(4) If the result is not as specified, inspect the switch, four wheel drive control ECU and transfer shift actuator assembly.

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 Symptom Related Diagnostic Procedures. Then check the combination meter Problem Symptoms Table.

(b) Center Differential Lock Indicator Light:

(1) Turn the engine switch On (IG).

(2) Change the center differential lock switch from Free to Lock.

(3) Check the center differential lock indicator light.

OK:

Center differential lock indicator light comes on

(3) If the result is not as specified, inspect the switches, four wheel drive control 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 Symptom Related Diagnostic Procedures. Then check the combination meter Problem Symptoms Table.

2. INSPECT FOUR WHEEL DRIVE CONTROL ECU (POWER SUPPLY)

(a) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(b) If the result is not as specified, inspect the harness, fuse 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 Removal.

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

Standard Resistance:





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

3. INSPECT FOUR WHEEL DRIVE CONTROL ECU (TRANSFER POSITION SWITCH)

(a) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(b) If the result is not as specified, check the power supply.

If the power supply is normal, inspect the transfer position switch 4WD Control Switch.

4. INSPECT FOUR WHEEL DRIVE CONTROL ECU (CENTER DIFFERENTIAL LOCK SWITCH))

(a) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(b) If the result is not as specified, check the power supply.

If the power supply is normal, inspect the center differential lock switch Center Differential Lock Switch.

5. INSPECT MULTI MODE TRANSFER SHIFT ACTUATOR

(a) Check the harness and connector between four wheel drive control ECU and transfer shift actuator assembly (multi mode transfer shift actuator).

(1) Disconnect the C34 actuator connector.

(2) Disconnect the G41 and G42 ECU connectors.

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





Text in Illustration





Standard Resistance:





(3) 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.

(b) Check the four wheel drive control ECU (multi mode transfer shift actuator circuit).

(1) Connect the G41 and G42 ECU connectors.

(2) Connect the C34 actuator connector.

(3) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(3) If the result is not as specified, determine if a malfunction is on the ECU side or actuator side by disconnecting the connector of the transfer shift actuator, and then check the ECU output voltage.

(c) Check the four wheel drive control ECU output voltage.

(1) Disconnect the C34 actuator connector.

(2) Connect the G41 and G42 ECU connectors.

(3) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(3) If the result is not as specified, replace the four wheel drive control ECU Removal.

If the voltage is normal, inspect the multi mode transfer shift actuator, because the voltage applied to the motor cannot be measured.

(d) Inspect the multi mode transfer shift actuator (transfer shift actuator assembly).

(1) Remove the transfer shift actuator assembly Disassembly.

(2) 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 FREE position.

NOTICE:
* 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 DEF relay on the main body ECU (instrument panel junction block).





Text in Illustration





1 After the LOCK to FREE switch is complete, inspect the center differential lock detection switch and limit switch.

Standard Resistance:





(3) 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 LOCK position.





Text in Illustration





1 After the FREE to LOCK switch is complete, inspect the center differential lock detection switch and limit switch.

Standard Resistance:





1 If the result is not as specified, replace the transfer shift actuator assembly Disassembly. If the transfer shift actuator assembly is normal, replace the four wheel drive control ECU Removal.

6. INSPECT HIGH-LOW TRANSFER SHIFT ACTUATOR

(a) Check the harness and connector between four wheel drive control ECU and transfer shift actuator (high-low transfer shift actuator).

(1) Disconnect the C34 actuator connector.

(2) Disconnect the G41 and G42 ECU connector.

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





Text in Illustration





Standard Resistance:





(3) 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.

(b) Check the four wheel drive control ECU (high-low transfer shift actuator circuit).

(1) Connect the G41 and G42 ECU connectors.

(2) Connect the C34 actuator connector.

(3) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(3) If the result is not as specified, determine if the malfunction is on the ECU side or actuator side by disconnecting the connector of the transfer shift actuator, and then check the ECU output voltage.

(c) Check the four wheel drive control ECU output voltage.

(1) Connect the G41 and G42 ECU connectors.

(2) Disconnect the C34 actuator connector.

(3) Measure the voltage according to the value(s) in the table below.





Standard Voltage:





Text in Illustration





(3) If the result is not as specified, replace the four wheel drive control ECU Removal.

If the voltage is normal, inspect the high-low transfer shift actuator, because the voltage applied to the motor cannot be measured.

(d) Inspect the high-low transfer shift actuator (transfer shift actuator assembly).

(1) Remove the transfer shift actuator assembly Disassembly.

(2) Check the HIGH to LOW switch.

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

NOTICE:
* 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 DEF relay on the main body ECU (instrument panel junction block).





Text in Illustration





1 After the HIGH to LOW switch is complete, inspect the limit switch.

Standard Resistance:





(3) Check the LOW to HIGH switch.

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





Text in Illustration





1 After the LOW to HIGH switch is complete, inspect the limit switch.

Standard Resistance:





1 If the result is not as specified, replace the transfer shift actuator assembly Disassembly. If the transfer shift actuator assembly is normal, replace the four wheel drive control ECU Removal.
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