Description
The mil (malfunction indicator lamp) is used to indicate vehicle malfunction detections by the ecm.
When the ignition switch is turned on, power is supplied to the mil circuit, and the ecm provides the circuit ground which illuminates the mil.
The mil operation can be checked visually: when the ignition switch is first turned on, the mil should be illuminated and should then turn off. If the mil remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the intelligent tester.
Wiring diagram

Inspection procedure

Standard: mil should go off.

Ok: mil is not illuminated.

Standard resistance (check for short)



Ok: mil should be illuminated.


Hint:
*: The intelligent tester cannot communicate with the ecm.


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Fuel pump control circuit
Mass air flow meterHow to proceed with troubleshooting
Notice:
Dtcs for the can communication system are as
follows: u0073, u0100, u0105, u0121, u0122, u0123,
u0124, u0126, u0129, c1280, c1296, c1297, and
b1499.
Refer to the troubleshooting procedures of each
system if dtcs regarding the can communication
system are not output.
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Ke ...