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 meterShift solenoid "d" performance (shift solenoid valve s4)
System description
The ecm uses signals from the output shaft speed sensor and input speed
sensor to detect the actual
gear position (1st, 2nd, 3rd or o/d gear).
Then the ecm compares the actual gear with the shift schedule in the ecm memory
to detect mechanical
problems of the shift s ...
Fog light switch
The fog lights secure excellent visibility in difficult driving
conditions,
such as in rain and fog.
(U.S.A.) Or (canada)
turns the fog lights off
Turns the fog lights on
Fog lights can be used when
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Abnormal temperature inside
Description
The tire pressure warning valve and transmitter measures tire internal
temperature as well as tire
pressure, and transmits the information to the tire pressure monitor receiver
along with the transmitter id.
If the measured temperature is out of the specified range, the tire ...