Toyota RAV4 (XA40) 2013-2018 Service Manual: Mil circuit
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
- Check that mil is illuminated
- Perform troubleshooting in accordance with the table below.
- Check whether mil turns off
- Connect the intelligent tester to the dlc3.
- Turn the ignition switch on and turn the tester on.
- Select the following menu items: diagnosis / enhanced obd ii / dtc info / current codes.
- Check if any dtcs have been stored. Note down any dtcs.
- Clear dtcs (see page es-35).
- Check if the mil goes off.
Standard: mil should go off.
- Check harness and connector (check for short in wire harness)
- Disconnect the a9 ecm connector.
- Turn the ignition switch on.
- Check that the mil is not illuminated.
Ok: mil is not illuminated.
- Reconnect the ecm connector.
- Check harness and connector (combination meter - ecm)
- Disconnect the a9 ecm connector.
- Disconnect the e19 combination meter connector.
- Measure the resistance.
Standard resistance (check for short)
- Reconnect the ecm connector.
- Reconnect the combination meter connector.
- Check that mil is illuminated
- Check if the mil is illuminated when the ignition switch is turned on.
Ok: mil should be illuminated.
- Check that engine starts
- Turn the ignition switch on.
- Start the engine.
Hint:
*: The intelligent tester cannot communicate with the ecm.
- Inspect combination meter assembly (mil circuit)
- Check the mil circuit (see page me-15).
Fuel pump control circuit
Description
When the engine is cranked, the starter relay drive signal output from the
star terminal of the ecm is
input into the sta terminal of the ecm, and ne signal generated by the
cranksha ...
Mass air flow meter
Components
...
Other materials:
On-vehicle inspection
Notice:
Perform the maf meter inspection according to the
procedures below.
Only replace the maf meter when both the long
ft#1 value and maf value in the data list (with the
engine stopped) are not within the normal operating
range.
Inspect mass air flow meter
Perform c ...
Emission inspection and maintenance (I/M) programs
Some states have vehicle
emission inspection programs
which include OBD
(On Board Diagnostics)
checks. The OBD system
monitors the operation of
the emission control system.
If the malfunction indicator
lamp comes on
The OBD system determines
that a problem exists somewhere
in the emission control
sy ...
Definition of terms
Terms
Definition
Monitor description
Description of what ecm monitors and how detects malfunctions
(monitoring purpose and
details).
Related dtcs
Group of diagnostic trouble codes that are output by ecm based on
same malfunction
detection logic.
...
