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

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 3.365,3.135 3.958,3.333 0.594,0.198 10 false 1 2.438,3.156 3.031,3.354 0.594,0.198 10 false 2 2.448,2.635 3.042,2.833 0.594,0.198 10 false 3 3.813,2.896 4.406,3.094 0.594,0.198 10 false METER 1.781,4.073 4.219,4.542 2.438,0.469 10 false from Certification ECU (Smart Key ECU Assembly)*1 1.76,4.708 4.406,4.896 2.646,0.188 10 false from Ignition Switch Assembly*2 0.958,5.146 3.604,5.333 2.646,0.188 10 false *1: w/ Smart Entry and Start System 0.948,5.438 3.594,5.625 2.646,0.188 10 false *2: w/o Smart Entry and Start System 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

Perform troubleshooting in accordance with the table below.

Result:

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

2.CHECK WHETHER DTC OUTPUT RECURS

5.CHECK THAT MIL IS ILLUMINATED

2.CHECK WHETHER DTC OUTPUT RECURS

Connect the GTS to the DLC3.

Turn the ignition switch to ON.

Turn the GTS on.

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

Powertrain > Engine and ECT > Trouble Codes: 50001 234

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.

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

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

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

Disconnect the A40 ECM connector.

Turn the ignition switch to ON.

Check that the MIL is not illuminated.

OK:: MIL is not illuminated.

Result:

Proceed to
OK
NG

REPLACE ECM

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>ECM>REMOVAL

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

Disconnect the combination meter assembly connector.

Disconnect the ECM connector.

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

REPLACE COMBINATION METER ASSEMBLY

Click hereVehicle Interior>METER / GAUGE / DISPLAY>COMBINATION METER>REMOVAL

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.CHECK THAT MIL IS ILLUMINATED

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

OK:: MIL should be illuminated.

Result:

Proceed to
OK
NG

CHECK FOR INTERMITTENT PROBLEMS

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>SFI SYSTEM>CHECK FOR INTERMITTENT PROBLEMS

6.CHECK THAT ENGINE STARTS

Turn the ignition switch to ON.

Start the engine.

Result:

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

HINT:: *: The GTS cannot communicate with the ECM.

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

GO TO VC OUTPUT CIRCUIT

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>SFI SYSTEM>VC Output Circuit

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

Disconnect the combination meter assembly connector.

Disconnect the ECM connector.

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

REPLACE COMBINATION METER ASSEMBLY

Click hereVehicle Interior>METER / GAUGE / DISPLAY>COMBINATION METER>REMOVAL

REPAIR OR REPLACE HARNESS OR CONNECTOR