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
Hint:
Use these procedures to troubleshoot the supplemental
restraint system.
*: Use the intelligent tester.
Vehicle brought to workshop
Inspect battery voltage*
Standard voltage:
11 to 14 v
If the voltage is below 11 v, recharge or replace the battery
before proceeding.
...
Problem symptoms table
Hint:
Use the table below to help determine the cause of the
problem symptom. The potential causes of the symptoms are
listed in order of probability in the "suspected area" column
of the table. Check each symptom by checking the suspected
areas in the order they are listed. Replace p ...
Terminals of ecu
Check transponder key amplifier
Disconnect the e5 amplifier connector.
Measure the resistance of the wire harness side
connector.
If the result is not as specified, there may be a
malfunction in the wire harness.
Reconnect the e5 amplifier connector.
Measure the resist ...