FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Fuel Injector Circuit

F: FUEL INJECTOR CIRCUIT

CAUTION:
- Check or repair only faulty parts.
- After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to Clear Diagnostic Trouble Codes.


Wiring Diagram:





WIRING DIAGRAM

8F1: CHECK OPERATION OF EACH FUEL INJECTOR.

While cranking the engine, check that each fuel injector emits "operating" sound. Use a sound scope or attach a screwdriver to injector for this check.

CHECK: Is the fuel injector emits "operating" sound?

YES: Check fuel pressure.

NO: Go to step 8F2.

8F2: CHECK POWER SUPPLY TO EACH FUEL INJECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connector from #1 cylinder fuel injector.
3. Turn ignition switch to ON.

Connector & Terminal - [#1 (E5) No.2 (+) - Engine Ground (-)]:





4. Measure power supply voltage between the fuel injector terminal and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 8F3.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between main relay and fuel injector connector
- Poor contact in main relay connector
- Poor contact in coupling connector (B22)
- Poor contact in fuel injector connector

8F3: CHECK POWER SUPPLY TO EACH FUEL INJECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connector from #2 cylinder fuel injector.
3. Turn ignition switch to ON.

Connector & Terminal - [#2 (E16) No.2 (+) - Engine Ground (-)]:





4. Measure power supply voltage between the fuel injector terminal and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 8F4.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between main relay and fuel injector connector
- Poor contact in main relay connector
- Poor contact in coupling connector (B22)
- Poor contact in fuel injector connector

8F4: CHECK POWER SUPPLY TO EACH FUEL INJECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connector from #3 cylinder fuel injector.
3. Turn ignition switch to ON.

Connector & Terminal - [#3 (E6) No.2 (+) - Engine Ground (-)]:





4. Measure power supply voltage between the fuel injector terminal and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 8F5.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between main relay and fuel injector connector
- Poor contact in main relay connector
- Poor contact in coupling connectors (B22)
- Poor contact in fuel injector connector

8F5: CHECK POWER SUPPLY TO EACH FUEL INJECTOR.

1. Turn ignition switch to OFF.
2. Disconnect connector from #4 cylinder fuel injector.
3. Turn ignition switch to ON.

Connector & Terminal - [#3 (E17) No.2 (+) - Engine Ground (-)]:





4. Measure power supply voltage between the fuel injector terminal and engine ground.

CHECK: Is the voltage more than 10 V?

YES: Go to step 8F6.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between main relay and fuel injector connector
- Poor contact in main relay connector
- Poor contact in coupling connectors (B22)
- Poor contact in fuel injector connector

8F6: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

1. Disconnect connector from ECM.

Connector & Terminal - [(B134) No.4 - (B136) No.2]:





2. Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance between 5 and 20 Ohms?

YES: Go to step 8F7.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between ECM and fuel injector connector
- Poor contact in coupling connector (B22)

8F7: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.4 - Chassis Ground]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance less than 1 Ohm?

YES: Repair ground short circuit in harness between ECM and fuel injector connector.

NO: Go to step 8F8.

8F8: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.13 - (B136) No.2]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance between 5 and 20 Ohms?

YES: Go to step 8F9.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between ECM and fuel injector connector
- Poor contact in coupling connector (B22)

8F9: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.13 - Chassis Ground]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance less than 1 Ohm?

YES: Repair ground short circuit in harness between ECM and fuel injector connector.

NO: Go to step 8F10.

8F10: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.14 - (B136) No.2]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance between 5 and 20 Ohms?

YES: Go to step 8F11.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between ECM and fuel injector connector
- Poor contact in coupling connector (B22)

8F11: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.14 - Chassis Ground]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance less than 1 Ohm?

YES: Repair ground short circuit in harness between ECM and fuel injector connector.

NO: Go to step 8F12.

8F12: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.15 - (B134) No.15 - (B136) No.2]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance between 5 and 20 Ohms?

YES: Go to step 8F13.

NO: Repair harness and connector.

NOTE: In this case, repair the following:
- Open circuit in harness between ECM and fuel injector connector
- Poor contact in coupling connector (B22)

8F13: CHECK HARNESS BETWEEN ECM AND FUEL INJECTOR CONNECTOR.

Connector & Terminal - [(B134) No.15 - Chassis Ground]:





Measure resistance of harness between ECM and fuel injector connector.

CHECK: Is the resistance less than 1 Ohm?

YES: Repair ground short circuit in harness between ECM and fuel injector connector.

NO: Go to step 8F14.

8F14: CHECK EACH FUEL INJECTOR.

1. Turn ignition switch to OFF.

Terminals - [No.1 - No.2]:





2. Measure resistance between each fuel injector terminals.

CHECK: Is the resistance between 5 and 20 Ohms?

YES: Go to step 8F15.

NO: Replace faulty fuel injector.

8F15: CHECK POOR CONTACT.
Check poor contact in ECM connector.

CHECK: Is there poor contact in ECM connector?

YES: Repair poor contact in ECM connector.

NO: Check crankshaft position sensor circuit.