2ZR-FE ENGINE CONTROL  SFI SYSTEM  MIL Circuit  


DESCRIPTION

The MIL (Malfunction Indicator Lamp) is used to indicate vehicle malfunctions detected by the ECM. When the ignition switch is turned to 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 turned to ON, the MIL should be illuminated and should turn off after engine is started. If the MIL remains illuminated or is not illuminated, conduct the following troubleshooting procedure using the GTS.

WIRING DIAGRAM

A298565E32
0.542,3.51 1.135,3.708 0.594,0.198 10 false FL MAIN 0.646,4.365 1.24,4.563 0.594,0.198 10 false Battery 1.521,2.885 2.115,3.083 0.594,0.198 10 false IG2 2.833,3.615 3.427,3.813 0.594,0.198 10 false IG2 3.375,2.646 3.969,2.844 0.594,0.198 10 false 5 3.396,3.146 3.99,3.344 0.594,0.198 10 false 1 2.458,3.156 3.052,3.354 0.594,0.198 10 false 2 2.469,2.635 3.063,2.833 0.594,0.198 10 false 3 3.813,2.896 4.406,3.094 0.594,0.198 10 false METER 2.385,4.052 5.073,4.271 2.688,0.219 10 false from Ignition Switch Assembly 6.042,5.052 6.635,5.25 0.594,0.198 10 false ECM 5.635,5.063 6.229,5.26 0.594,0.198 10 false A40 2.656,0.698 3.25,0.896 0.594,0.198 10 false 39 4.406,0.688 5,0.885 0.594,0.198 10 false 11 4.031,0.927 4.625,1.125 0.594,0.198 10 false CHK 2.917,0.927 3.51,1.125 0.594,0.198 10 false IG+ 2.563,1.25 3.156,1.448 0.594,0.198 10 false E43 2.573,1.417 4.542,1.635 1.969,0.219 10 false Combination Meter Assembly 5.094,0.688 5.688,0.885 0.594,0.198 10 false 27 5.344,0.688 5.938,0.885 0.594,0.198 10 false W

CAUTION / NOTICE / HINT

NOTICE:

Inspect the fuses for circuits related to this system before performing the following procedure.


PROCEDURE

1.CHECK THAT MIL IS ILLUMINATED
a.

Perform troubleshooting in accordance with the table below.


Result:
Result Proceed to
MIL remains on A
MIL does not illuminate B



A

2.CHECK WHETHER DTC OUTPUT RECURS

B

5.CHECK THAT MIL IS ILLUMINATED
2.CHECK WHETHER DTC OUTPUT RECURS
a.

Connect the GTS to the DLC3.


b.

Turn the ignition switch to ON.


c.

Turn the GTS on.


d.

Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

Powertrain > Engine and ECT > Trouble Codes
50001 234

e.

Check if any DTCs have been detected. Note down any DTCs.

Result:
Result Proceed to
No DTC detected A
Any DTCs detected B


HINT:

Check for detected DTCs output from other ECUs which relate to the MIL.




A

3.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)

B

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

3.CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT IN WIRE HARNESS)
a.

Disconnect the A40 ECM connector.


b.

Turn the ignition switch to ON.


c.

Check that the MIL is not illuminated.

OK:

MIL is not illuminated.



Result:
Proceed to
OK
NG



OK

NG

4.CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
4.CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
a.

Disconnect the combination meter assembly connector.


b.

Disconnect the ECM connector.


c.

Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Connection Condition Specified Condition
E43-11 (CHK) or A40-27 (W) - Body ground Always 10 kΩ or higher



Result:
Proceed to
OK
NG



OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.CHECK THAT MIL IS ILLUMINATED
a.

Check if the MIL is illuminated when the ignition switch is turned to ON.

OK:

MIL should be illuminated.



Result:
Proceed to
OK
NG



OK

NG

6.CHECK THAT ENGINE STARTS
6.CHECK THAT ENGINE STARTS
a.

Turn the ignition switch to ON.


b.

Start the engine.

Result:
Result Proceed to
Engine starts A
Engine does not start* B


HINT:

*: The GTS cannot communicate with the ECM.




A

7.CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)

B

7.CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ECM)
a.

Disconnect the combination meter assembly connector.


b.

Disconnect the ECM connector.


c.

Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Connection Condition Specified Condition
E43-11 (CHK) - A40-27 (W) Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

REPLACE COMBINATION METER ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR