GSIC - Global Service Information Center

### SFI SYSTEM > Fuel Injector Circuit

## for Preparation Click here

## DESCRIPTION

The fuel injectors are located on the intake manifold. They inject fuel into the cylinders based on the signals from the ECM.

## WIRING DIAGRAM

## INSPECTION PROCEDURE

1.CHECK ECM (#10, #20, #30, #40 VOLTAGE)

1. Turn the ignition switch ON.

1. Measure the voltage of the ECM connectors.

   Standard voltage:

     Tester Connection | Specified Condition
     E11-6 (#10) - E12-7 (E01) | 9 to 14 V
     E11-5 (#20) - E12-7 (E01) | 9 to 14 V
     E11-2 (#30) - E12-7 (E01) | 9 to 14 V
     E11-1 (#40) - E12-7 (E01) | 9 to 14 V

   HINT:
     Reference: Inspection using the oscilloscope.
     Check the waveform of the ECM connector.

   Tester Connection | Specified Condition
   E11-6 (#10) - E12-7 (E01) | Correct waveform is as shown
   E11-5 (#20) - E12-7 (E01) | Correct waveform is as shown
   E11-2 (#30) - E12-7 (E01) | Correct waveform is as shown
   E11-1 (#40) - E12-7 (E01) | Correct waveform is as shown

   Tool Setting | Condition
   20V/DIV., 100 or 1 msec./DIV. | Idling

| OK |

Go to step 6

NG |

2.INSPECT FUEL INJECTOR ASSEMBLY (RESISTANCE)

1. Inspect the fuel injector (Click here).

| NG |

REPLACE FUEL INJECTOR ASSEMBLY

OK |

3.INSPECT FUSE (INJ)

1. Remove the INJ fuse from the instrument panel junction block.

1. Measure the resistance of the fuse.

   Standard:
     Below 1 Ω

| NG |

CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE

OK |

4.CHECK WIRE HARNESS OF MISFIRING CYLINDER (INJECTOR - ECM, INJECTOR - INJ FUSE)

1. Check the wire harness between the injector and ECM.

   1. Disconnect the F5, F6, F7 and/or F8 injector connectors.

   2. Disconnect the E11 ECM connector.

   3. Measure the resistance of the wire harness side connectors.

      Standard resistance:

        Tester Connection | Specified Condition
        F5-2 - E11-6 (#10) | Below 1 Ω
        F6-2 - E11-5 (#20) | Below 1 Ω
        F7-2 - E11-2 (#30) | Below 1 Ω
        F8-2 - E11-1 (#40) | Below 1 Ω
        F5-2 or E11-6 (#10) - Body ground | 10 kΩ or higher
        F6-2 or E11-5 (#20) - Body ground | 10 kΩ or higher
        F7-2 or E11-2 (#30) - Body ground | 10 kΩ or higher
        F8-2 or E11-1 (#40) - Body ground | 10 kΩ or higher

1. Check the wire harness between the injector and INJ fuse.

   1. Disconnect the F5, F6, F7 and F8 injector connectors.

   2. Remove the INJ fuse from the instrument panel junction block.

   3. Measure the resistance of the wire harness side connectors.

      Standard resistance:

        Tester Connection | Specified Condition
        F5-1 - J/B INJ fuse terminal 2 | Below 1 Ω
        F6-1 - J/B INJ fuse terminal 2 | Below 1 Ω
        F7-1 - J/B INJ fuse terminal 2 | Below 1 Ω
        F8-1 - J/B INJ fuse terminal 2 | Below 1 Ω
        F5-1 or J/B INJ fuse terminal 2 - Body ground | 10 kΩ or higher
        F6-1 or J/B INJ fuse terminal 2 - Body ground | 10 kΩ or higher
        F7-1 or J/B INJ fuse terminal 2 - Body ground | 10 kΩ or higher
        F8-1 or J/B INJ fuse terminal 2 - Body ground | 10 kΩ or higher

| NG |

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK |

5.CHECK WIRE HARNESS (IGNITION SWITCH - INJ FUSE)

1. Disconnect the I6 ignition switch connector.

1. Remove the INJ fuse from the instrument panel junction block.

1. Measure the resistance of the wire harness side connectors.

   Standard resistance:

     Tester Connection | Specified Condition
     I6-6 (IG2) - J/B INJ fuse terminal 1 | Below 1 Ω
     I6-6 (IG2) or J/B INJ fuse terminal 1 - Body ground | 10 kΩ or higher

| NG |

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK |

CHECK FOR ECM POWER SOURCE CIRCUIT

6.CHECK WIRE HARNESS (ECM - BODY GROUND)

1. Disconnect the E12 ECM connector.

1. Measure the resistance of the wire harness side connector.

   Standard resistance:

     Tester Connection | Specified Condition
     E12-7 (E01) - Body ground | Below 1 Ω
     E12-6 (E02) - Body ground | Below 1 Ω

| NG |

REPAIR OR REPLACE HARNESS AND CONNECTOR

OK |

7.INSPECT FUEL INJECTOR ASSEMBLY (CHECK FUEL INJECTION VOLUME)

1. Inspect the fuel injector (Click here).

| NG |

REPLACE FUEL INJECTOR ASSEMBLY

OK |

PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE