Inspection Procedure

HINT:

Check the condition of each related circuit connector before troubleshooting (See ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).

1. CHECK FOR DTC 
   1. Check the output DTC (See DTC CHECK / CLEAR  ).

      Result 

      RESULT REFERENCE CHART
      
      

      Result	Proceed to
      Neither CAN communication system DTC nor 4WD control system DTC is output	A
      CAN communication DTC is output	B
      4WD control system DTC is output	C

      HINT:

      When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.

      B: REPAIR CIRCUIT INDICATOR BY OUTPUT CODE (CAN COMMUNICATION SYSTEM)  (See DIAGNOSTIC TROUBLE CODE CHART )

      C: REPAIR CIRCUIT INDICATOR BY OUTPUT CODE (ACTIVE TORQUE CONTROL 4WD SYSTEM)  (See DIAGNOSTIC TROUBLE CODE CHART  )

      A: Go to Next Step 

2. CHECK IF 4WD CONTROL ECU CONNECTOR IS SECURELY CONNECTED 
   1. Check if the skid control ECU connector is securely connected.

      OK: 

      The connector is securely connected  .

      NG: CONNECT CONNECTOR TO ECU CORRECTLY 

      OK: Go to Next Step 

3. CHECK BATTERY 
   1. Check the battery voltage.

      Standard Voltage: 

      11 to 14 V 

      Result 

      RESULT REFERENCE CHART
      
      

      Result	Proceed to
      OK	A
      NG	B

      B: CHECK OR REPLACE CHARGING SYSTEM AND BATTERY  (See SYSTEM DIAGRAM )

      A: Go to Next Step 

4. PERFORM ACTIVE TEST (4WD WARNING LIGHT) 
   1. Warm up the engine.
   2. Turn the ignition switch off.
   3. Connect the Techstream to the DLC3.
   4. Turn the ignition switch to ON.
   5. Turn the Techstream on.
   6. Enter the following menus: Chassis / 4WD / Active Test.
   7. According to the display on the Techstream, perform the Active Test.

      Chassis / 4WD / Active Test 

      ACTIVE TEST REFERENCE CHART
      
      

      Tester Display	Test Part	Control Range	Diagnostic Note
      4WD Light	4WD Warning light	Warning light is ON/OFF	Observer combination meter

      OK: 

      The 4WD warning light turns off  .

      NG: Go to Next Step 

      OK: REPLACE 4WD CONTROL ECU  (See REMOVAL  )

5. CHECK WIRE HARNESS OR CONNECTOR (4WD CONTROL ECU - BATTERY) 
   1. Disconnect the ECU connector.
   2. Turn the ignition switch to ON.
   3. Measure the voltage of the wire harness side connector.

      Standard Voltage 

      STANDARD VOLTAGE
      
      

      Tester Connection	Condition	Specified Condition
      E17-11 (IG1)-Body Ground	Ignition switch ON	11 to 14 V

      Fig 1: Checking Wire Harness Or Connector (4WD Control ECU - Battery)

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (4WD CONTROL ECU - BATTERY) 

      OK: Go to Next Step 

6. CHECK WIRE HARNESS OR CONNECTOR (4WD CONTROL ECU - BODY GROUND) 
   1. Disconnect the ECU connector.
   2. Measure the resistance of the wire harness side connector.

      Standard Resistance 

      STANDARD RESISTANCE
      
      

      Tester Connection	Condition	Specified Condition
      E17-23 (GND) - Body Ground	Always	Below 1 Ω

      Fig 2: Checking Wire Harness Or Connector (4WD Control ECU - Body Ground)

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (4WD CONTROL ECU - BODY GROUND) 

      OK: Go to Next Step 

7. CHECK 4WD CONTROL ECU 
   1. Connect the ECU connector.
   2. Turn the ignition switch to ON.
   3. Measure the voltage of the wire harness side connector.

      Standard Voltage 

      STANDARD VOLTAGE
      
      

      Tester Connection	Condition	Specified Condition
      E17-11 (IG1) - Body Ground	Ignition switch ON	11 to 14 V

      Fig 3: Checking 4WD Control ECU

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPLACE 4WD CONTROL ECU  (See REMOVAL  )

      OK: REPLACE COMBINATION METER  (See COMBINATION METER )