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 meterTerminals of ecu
Check tire pressure warning ecu
Disconnect the e56 ecu connector.
Measure the voltage and resistance of the wire
harness side connector.
If the result is not as specified, there may be a
malfunction on the wire harness side.
Reconnect the e56 ecu connector.
Measure the ...
Reassembly
V
Attach the 7 outside moulding retainers to install the
extension.
Install front bumper extension rh (for wide
body)
Hint:
Use the same procedures described for the lh side.
Install front bumper hole cover lh (w/o fog
light)
Install the bumper hole cover with ...
Terminals of ecm
Check ecm
Measure the voltage of the ecm connector.
Hint:
Each ecm terminal's standard voltage is shown in
the table below.
In the table, first follow the information under
"condition". Look under "symbols (terminal no.)"
For the terminals to be inspected. ...