2ZR-FE ENGINE CONTROL  SFI SYSTEM  ECM Power Source Circuit  


DESCRIPTION

When the ignition switch is turned to ON, the battery voltage is applied to IGSW of the ECM. The output signal from the MREL terminal of the ECM causes a current to flow to the coil, closing the contacts of the EFI-MAIN relay and supplying power to terminals +B and +B2 of the ECM.

WIRING DIAGRAM

A327850E02
1.521,1.417 2.75,1.615 1.229,0.198 10 false EFI-MAIN 1.396,2.458 2.625,2.656 1.229,0.198 10 false ECU-B NO. 3 1.635,3.146 2.01,3.365 0.375,0.219 10 false IG2 0.896,4.719 1.271,4.938 0.375,0.219 10 false AM2 0.521,5.146 1.75,5.344 1.229,0.198 10 false FL MAIN 0.677,5.99 1.906,6.188 1.229,0.198 10 false Battery 1.417,5.052 3.01,5.323 1.594,0.271 10 false Ignition Switch Assembly 1.427,4.906 1.802,5.125 0.375,0.219 10 false E4 1.458,4.448 1.833,4.667 0.375,0.219 10 false 4 2.76,4.448 3.135,4.667 0.375,0.219 10 false 3 1.635,4.448 2.01,4.667 0.375,0.219 10 false AM2 2.427,4.458 2.802,4.677 0.375,0.219 10 false IG2 3.969,3.792 4.344,4.01 0.375,0.219 10 false IG2 3.604,3.344 3.979,3.563 0.375,0.219 10 false 2 4.385,3.344 4.76,3.563 0.375,0.219 10 false 1 3.615,2.844 3.99,3.063 0.375,0.219 10 false 3 4.375,2.833 4.75,3.052 0.375,0.219 10 false 5 3.729,2.083 4.958,2.281 1.229,0.198 10 false EFI-MAIN 3.594,1.667 3.969,1.885 0.375,0.219 10 false 2 4.375,1.656 4.75,1.875 0.375,0.219 10 false 1 3.594,1.167 3.969,1.385 0.375,0.219 10 false 5 4.385,1.156 4.76,1.375 0.375,0.219 10 false 3 4.49,1.417 5.719,1.615 1.229,0.198 10 false EFI NO. 1 4.938,3.104 5.313,3.323 0.375,0.219 10 false IGN 5.792,0.771 6.167,0.99 0.375,0.219 10 false A40 5.781,1.271 6.156,1.49 0.375,0.219 10 false A40 5.792,1.771 6.167,1.99 0.375,0.219 10 false A40 5.792,2.292 6.167,2.51 0.375,0.219 10 false A40 5.792,2.948 6.167,3.167 0.375,0.219 10 false A40 5.792,5.073 6.167,5.292 0.375,0.219 10 false B33 5.813,4.896 6.188,5.115 0.375,0.219 10 false 16 5.875,0.583 6.25,0.802 0.375,0.219 10 false 2 5.875,1.094 6.25,1.313 0.375,0.219 10 false 3 5.854,1.583 6.229,1.802 0.375,0.219 10 false 46 5.865,2.104 6.24,2.323 0.375,0.219 10 false 1 5.833,2.771 6.208,2.99 0.375,0.219 10 false 37 6.156,0.75 6.531,0.969 0.375,0.219 10 false +B 6.146,1.25 6.521,1.469 0.375,0.219 10 false +B2 6.156,1.771 6.646,2.01 0.49,0.24 10 false MREL 6.156,2.292 6.646,2.531 0.49,0.24 10 false BATT 6.156,2.948 6.646,3.188 0.49,0.24 10 false IGSW 6.156,5.063 6.646,5.302 0.49,0.24 10 false E1 6.344,5.99 6.833,6.229 0.49,0.24 10 false ECM

CAUTION / NOTICE / HINT

NOTICE:

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


PROCEDURE

1.CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)
a.

Disconnect the ECM connector.


b.

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

Standard Resistance:
Tester Connection Condition Specified Condition
B33-16 (E1) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

2.CHECK TERMINAL VOLTAGE (IGSW TERMINAL VOLTAGE)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

2.CHECK TERMINAL VOLTAGE (IGSW TERMINAL VOLTAGE)
A255690C53
0.323,1.063 0.75,1.323 0.427,0.26 1.854,1.365 1.854,1.906 false 0.177,0.156 0.521,0.448 0.344,0.292 10 false *a 1.708,1.927 2.333,2.094 0.625,0.167 10 false IGSW 0.417,1.115 0.771,1.375 0.354,0.26 10 false A40
*a Front view of wire harness connector
(to ECM)


a.

Disconnect the ECM connector.


b.

Turn the ignition switch to ON.


c.

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

Standard Voltage:
Tester Connection Condition Specified Condition
A40-37 (IGSW) - Body ground Ignition switch ON 11 to 14 V



Result:
Proceed to
OK
NG



OK

3.INSPECT EFI-MAIN RELAY

NG

7.INSPECT IG2 RELAY
3.INSPECT EFI-MAIN RELAY
a.

Inspect the EFI-MAIN relay.

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>RELAY>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

4.CHECK HARNESS AND CONNECTOR (ECM - EFI-MAIN RELAY)

NG

REPLACE EFI-MAIN RELAY

4.CHECK HARNESS AND CONNECTOR (ECM - EFI-MAIN RELAY)
a.

Disconnect the ECM connector.


b.

Remove the EFI-MAIN relay from the engine room relay block and junction block assembly.


c.

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

Standard Resistance:
Tester Connection Condition Specified Condition
A40-46 (MREL) - 1 (EFI-MAIN relay) Always Below 1 Ω
A40-2 (+B) - 3 (EFI-MAIN relay) Always Below 1 Ω
A40-3 (+B2) - 3 (EFI-MAIN relay) Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

5.CHECK TERMINAL VOLTAGE (POWER SOURCE OF EFI-MAIN RELAY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.CHECK TERMINAL VOLTAGE (POWER SOURCE OF EFI-MAIN RELAY)
A330874C01
0.198,1.698 0.51,1.896 0.313,0.198 10 false *2 0.135,0.146 0.448,0.344 0.313,0.198 10 false *1
*1 Engine Room Relay Block and Junction Block Assembly
*2 EFI-MAIN Relay


a.

Remove the EFI-MAIN relay from the engine room relay block and junction block assembly.


b.

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

Standard Voltage:
Tester Connection Condition Specified Condition
5 (EFI-MAIN relay) - Body ground Always 11 to 14 V



Result:
Proceed to
OK
NG



OK

6.CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - BODY GROUND)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN RELAY - BATTERY)

6.CHECK HARNESS AND CONNECTOR (EFI-MAIN RELAY - BODY GROUND)
a.

Remove the EFI-MAIN relay from the engine room relay block and junction block assembly.


b.

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

Standard Resistance:
Tester Connection Condition Specified Condition
2 (EFI-MAIN relay) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>SFI SYSTEM>PROBLEM SYMPTOMS TABLE


NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.INSPECT IG2 RELAY
a.

Inspect the IG2 relay.

Click hereEngine / Hybrid System>2ZR-FE ENGINE CONTROL>RELAY>ON-VEHICLE INSPECTION


Result:
Proceed to
OK
NG



OK

8.CHECK HARNESS AND CONNECTOR (ECM - IG2 RELAY)

NG

REPLACE IG2 RELAY

8.CHECK HARNESS AND CONNECTOR (ECM - IG2 RELAY)
a.

Disconnect the ECM connector.


b.

Remove the IG2 relay from the engine room relay block and junction block assembly.


c.

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

Standard Resistance:
Tester Connection Condition Specified Condition
A40-37 (IGSW) - 5 (IG2 relay) Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

9.CHECK TERMINAL VOLTAGE (POWER SOURCE OF IG2 RELAY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

9.CHECK TERMINAL VOLTAGE (POWER SOURCE OF IG2 RELAY)
A330870C01
0.083,0.156 0.396,0.354 0.313,0.198 10 false *1 0.208,1.719 0.521,1.917 0.313,0.198 10 false *2
*1 Engine Room Relay Block and Junction Block Assembly
*2 IG2 Relay


a.

Remove the IG2 relay from the engine room relay block and junction block assembly.


b.

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

Standard Voltage:
Tester Connection Condition Specified Condition
3 (IG2 relay) - Body ground Always 11 to 14 V



Result:
Proceed to
OK
NG



OK

10.CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (IG2 RELAY - BATTERY)

10.CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND)
a.

Remove the IG2 relay from the engine room relay block and junction block assembly.


b.

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

Standard Resistance:
Tester Connection Condition Specified Condition
2 (IG2 relay) - Body ground Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

11.INSPECT IGNITION SWITCH ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

11.INSPECT IGNITION SWITCH ASSEMBLY
a.

Inspect the ignition switch assembly.

Click hereEngine / Hybrid System>2ZR-FE STARTING>IGNITION SWITCH>INSPECTION


Result:
Proceed to
OK
NG



OK

12.CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - IG2 RELAY)

NG

REPLACE IGNITION SWITCH ASSEMBLY

Click hereEngine / Hybrid System>2ZR-FE STARTING>IGNITION SWITCH>REMOVAL


12.CHECK HARNESS AND CONNECTOR (IGNITION SWITCH ASSEMBLY - IG2 RELAY)
a.

Disconnect the ignition switch assembly connector.


b.

Remove the IG2 relay from the engine room relay block and junction block assembly.


c.

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

Standard Resistance:
Tester Connection Condition Specified Condition
E4-3 (IG2) - 1 (IG2 relay) Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

REPAIR OR REPLACE HARNESS OR CONNECTOR (IGNITION SWITCH ASSEMBLY - BATTERY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR