MIL Circuit: Wiring Diagram

1. Perform troubleshooting in accordance with the chart below.

   Result 

B : GO TO STEP   4 

A : Go to next step 

1. Connect the intelligent tester to the DLC3.
2. Turn the ignition switch ON.
3. Turn the tester ON.
4. Check whether any DTCs have been stored (see DTC CHECK / CLEAR  ). Note them down if necessary.
5. Clear DTCs (see DTC CHECK / CLEAR  ).
6. Check if the MIL turns off.

OK: 

MIL should turn off. 

OK : REPAIR CIRCUIT INDICATED BY OUTPUT DTC 

NG 

1. Disconnect the E4 ECM connector.
2. Turn the ignition switch ON.
3. Check that the MIL is not illuminated.

OK: 

MIL is not illuminated 

OK : REPLACE ECM 

Fig 2: Disconnecting E4 ECM Connector

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NG : CHECK AND REPAIR HARNESS AND CONNECTOR (COMBINATION METER - ECM) 

1. Check if the MIL is illuminated when the ignition switch is turned ON.

OK: 

MIL should be illuminated. 

OK : SYSTEM OK 

NG 

1. Turn the ignition switch ON.
2. Start the engine.

HINT:

*: The intelligent tester cannot communicate with the ECM.

B : GO TO VC OUTPUT CIRCUIT 

A : Go to next step 

1. See the combination meter troubleshooting procedure (see HOW TO PROCEED WITH TROUBLESHOOTING ).

NG : REPAIR OR REPLACE BULB OR COMBINATION METER ASSEMBLY 

OK : CHECK AND REPAIR HARNESS AND CONNECTOR (COMBINATION METER - ECM)