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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Hint:
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problem analysis must be carried out. A simulation of the
same or similar conditions and environment in which the
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Parts location
System diagram
On-vehicle inspection
Hint:
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Diagnosis system
Description
Key reminder warning system data can be read
through the data link connector 3 (dlc3) of the
vehicle. When the system seems to be
malfunctioning, use the intelligent tester (with can
vim) to check for malfunctions and perform repairs.
Check dlc3
The vehi ...