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 meterIf your vehicle needs to be
towed
If towing is necessary, we
recommend having your
vehicle towed by your
Toyota dealer or commercial
towing service, using a
wheel-lift type truck or flatbed
truck.
Use a safety chain system
for all towing, and abide by
all state/provincial and local
laws.
Situations when it is necessary
to contact d ...
Fail-safe chart
Fail safe operation
If there is a problem with any sensor signals or
actuator systems, the skid control ecu prohibits the
power supply to the abs and traction actuator
and informs the ecm of vsc system failure.
The abs and traction actuator turns off the
solenoids and the ecm sh ...
Data list / active test
Hint:
Using the intelligent tester's data list allows switch, sensor,
actuator and other item values to be read without removing
any parts. Reading the data list early in troubleshooting is
one way to save time.
Data list for occupant classification ecu
Connect the intelligent test ...