SFI SYSTEM Fuel Injector Circuit

DESCRIPTION

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

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK TERMINAL VOLTAGE (POWER SOURCE OF FUEL INJECTOR ASSEMBLY)

   
   
   1. 

      Text in Illustration

      *a	Front view of wire harness connector (to Fuel Injector Assembly)

      Disconnect the fuel injector assembly connectors.

   2. Turn the ignition switch to ON (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition C1-2 - Body ground Ignition switch ON (IG) 11 to 14 V C2-2 - Body ground Ignition switch ON (IG) 11 to 14 V C3-2 - Body ground Ignition switch ON (IG) 11 to 14 V C4-2 - Body ground Ignition switch ON (IG) 11 to 14 V

   
   

   NG

   CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - NO. 1 INTEGRATION RELAY) Click here

   OK

2. INSPECT FUEL INJECTOR ASSEMBLY

   
   

   1. Check the fuel injector assembly Click here.

      Tech Tips

      Perform "Inspection After Repair" after replacing the fuel injector assembly Click here.

   
   

   NG

   REPLACE FUEL INJECTOR ASSEMBLY Click here

   OK

3. CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - ECM)

   
   

   1. Disconnect the C1, C2, C3 and C4 fuel injector assembly connectors.

   2. Disconnect the C10 ECM connector (for LHD).

   3. Disconnect the C9 ECM connector (for RHD).

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

      Standard Resistance
      for LHD Tester Connection Condition Specified Condition C1-1 - C10-20 (#10) Always Below 1 Ω C2-1 - C10-17 (#20) Always Below 1 Ω C3-1 - C10-18 (#30) Always Below 1 Ω C4-1 - C10-19 (#40) Always Below 1 Ω C1-1 or C10-20 (#10) - Body ground Always 10 kΩ or higher C2-1 or C10-17 (#20) - Body ground Always 10 kΩ or higher C3-1 or C10-18 (#30) - Body ground Always 10 kΩ or higher C4-1 or C10-19 (#40) - Body ground Always 10 kΩ or higher
      for RHD Tester Connection Condition Specified Condition C1-1 - C9-20 (#10) Always Below 1 Ω C2-1 - C9-17 (#20) Always Below 1 Ω C3-1 - C9-18 (#30) Always Below 1 Ω C4-1 - C9-19 (#40) Always Below 1 Ω C1-1 or C9-20 (#10) - Body ground Always 10 kΩ or higher C2-1 or C9-17 (#20) - Body ground Always 10 kΩ or higher C3-1 or C9-18 (#30) - Body ground Always 10 kΩ or higher C4-1 or C9-19 (#40) - Body ground Always 10 kΩ or higher

   
   

   OK

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

4. CHECK HARNESS AND CONNECTOR (FUEL INJECTOR ASSEMBLY - NO. 1 INTEGRATION RELAY)

   
   

   1. Disconnect the C1, C2, C3 and C4 fuel injector assembly connectors.

   2. Remove the No. 1 integration relay from the No. 2 engine room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition C1-2 - 2D-4 Always Below 1 Ω C2-2 - 2D-4 Always Below 1 Ω C3-2 - 2D-4 Always Below 1 Ω C4-2 - 2D-4 Always Below 1 Ω C1-2 or 2D-4 - Body ground Always 10 kΩ or higher C2-2 or 2D-4 - Body ground Always 10 kΩ or higher C3-2 or 2D-4 - Body ground Always 10 kΩ or higher C4-2 or 2D-4 - Body ground Always 10 kΩ or higher

   
   

   OK

   CHECK ECM POWER SOURCE CIRCUIT Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR