MIL Circuit: Wiring Diagram

Fig 1: Wiring Diagram - MIL Circuit

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

Troubleshoot each problem symptom in accordance with the chart below.

1. CHECK MIL CONDITION (WHETHER MIL TURNS OFF) 
   1. Connect the intelligent tester to the DLC3.
   2. Turn the engine switch on (IG).
   3. Turn the tester on.
   4. Check whether any DTCs have been stored (See DIAGNOSIS SYSTEM  ). Note them down if necessary.
   5. Clear DTCs (See DIAGNOSIS SYSTEM  ).
   6. Check if the MIL turns off.

      OK: MIL turns off. 

   OK : REPAIR CIRCUIT INDICATED BY OUTPUT DTC 

   NG : GO TO NEXT STEP 

2. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the A6 ECM connector.
   2. Turn the engine switch on (IG).
   3. Check the MIL is not illuminated.
      Fig 2: Identifying A6 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: MIL is not illuminated. 

   4. Reconnect the ECM connector.

   OK : REPLACE ECM 

   NG : GO TO NEXT STEP 

3. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
   1. Disconnect the A6 ECM connector.
   2. Disconnect the J35 combination meter connector.
   3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      W (A6-8) - EFI (J35-12)	Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      W (A6-8) or EFI (J35-12) - Body ground	10 kΩ or higher

      Fig 3: Identifying A6 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK : REPAIR OR REPLACE COMBINATION METER ASSEMBLY 

   NG : REPAIR OR REPLACE HARNESS OR CONNECTOR 

4. CHECK MIL (MIL IS ILLUMINATED) 
   1. Check if the MIL is illuminated when the engine switch is turns on (IG).

      OK: MIL is illuminated. 

   OK : SYSTEM IS OK 

   NG : GO TO NEXT STEP 

5. CHECK HARNESS AND CONNECTOR 
   1. Disconnect the A6 ECM connector.
   2. Turn the engine switch on (IG).
   3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      VOLTAGE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      W (A6-8) - Body ground	10 to 14 V

      Fig 4: Identifying A6 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   4. Reconnect the ECM connector.

   OK : REPLACE ECM 

   NG : go to next step 

6. CHECK HARNESS AND CONNECTOR (COMBINATION METER - ECM) 
   1. Disconnect the A6 ECM connector.
   2. Disconnect the J35 combination meter connector.
   3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      W (A6-8) - EFI (J35-12)	Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFICATION
      
      

      Tester Connection	Specified Condition
      W (A6-8) or EFI (J35-12) - Body ground	10 kΩ or higher

      Fig 5: Identifying A6 ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK : REPAIR OR REPLACE COMBINATION METER ASSEMBLY 

   NG : REPAIR OR REPLACE HARNESS OR CONNECTOR