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 meterKnock sensor 1 circuit
Description
Flat type knock sensors (non-resonant type) have structures that can detect
vibrations over a wide band
of frequencies: between approximately 6 khz and 15 khz.
A knock sensor is fitted onto the engine block to detect engine knocking.
The knock sensor contains a piezoelectri ...
Trouble in passenger airbag on / off indicator
Description
The occupant classification system detects the front passenger seat condition
and then indicates whether
the front passenger airbag is activated or not through the passenger airbag on /
off indicator
illumination.
The passenger airbag on / off indicator illumination changes dep ...
Mass air flow circuit range / performance problem
Description
Refer to dtc p0100 (see page es-86).
Monitor description
The maf meter is a sensor that measures the amount of air flowing through the
throttle valve. The ecm
uses this information to determine the fuel injection time and to provide an
appropriate air-fuel ratio. Inside
...