4WD Warning Light Remains ON: Procedure

1. Refer to DTC CHECK / CLEAR .

   Result

   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 → See step   8 

C → See step   9 

A: Go to next step 

1. Check if the 4WD control ECU connector is securely connected.

   OK

   The connector is securely connected.

NG → CONNECT CONNECTOR TO ECU CORRECTLY 

OK: Go to next step 

1. Check the battery voltage.

   Standard Voltage

   11 to 14 V

   Result

   Result	Proceed to
   OK	A
   NG	B

B → See step   10 

A: Go to next step 

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
   
   

   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 → See step   5 

OK → See step   11 

1. Disconnect the 4WD control ECU connector.
   Fig 1: Checking Wire Harness (4WD Control ECU - Battery)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch to ON.
3. Measure the voltage of the wire harness side connector.

   Standard Voltage

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

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

OK: Go to next step 

1. Disconnect the 4WD control ECU connector.
   Fig 2: Checking Wire Harness (4WD Control ECU - Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance of the wire harness side connector.

   Standard Resistance

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

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

OK: Go to next step 

1. Connect the 4WD control ECU connector.
   Fig 3: Checking 4WD Control ECU

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch to ON.
3. Measure the voltage of the wire harness side connector.

   Standard Voltage

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

NG → See step   11 

OK → See step   12