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Fuel Injector Operation Inspection

If simulation function of M-MDS is used:

FUEL INJECTOR OPERATION INSPECTION PROCEDURE

STEP INSPECTION RESULTS ACTION
1 Start the engine and warm it up until normal operating temperature.
Access the INJ_1, INJ_2, INJ_3 and INJ_4 PIDs using the M-MDS.
(See ON-BOARD DIAGNOSTIC TEST .)
Turn the fuel injector from on to off using the PIDs each cylinder.
Does the engine speed drop?
Yes Fuel injector work properly.
No Go to the next step.
2 Disconnect the fuel injector that the engine speed does not drop at Step 1.
Inspect open or short circuit between suspect fuel injector terminal B (wiring harness-side) and fuel pump relay terminal C (wiring harness-side).
Is there any malfunction?
Yes Repair or replace the wiring harness for a possible open or short circuit.
No Go to the next step.
3 Inspect for open or short circuit between the following terminals (wiring harness-side):
  • Fuel injector No. 1 terminal A-PCM terminal 2BB
  • Fuel injector No. 2 terminal A-PCM terminal 2BC
  • Fuel injector No. 3 terminal A-PCM terminal 2BD
  • Fuel injector No. 4 terminal A-PCM terminal 2AZ

Is there any malfunction?
Yes Repair or replace the wiring harness for a possible open or short circuit.
No Go to the next step.
4 Inspect the suspected fuel injector.
(See FUEL INJECTOR INSPECTION .)
Is there any malfunction?
Yes Replace the suspected fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
No Replace the PCM.
(See PCM REMOVAL/INSTALLATION .)

If simulation function of M-MDS is not used:

FUEL INJECTOR OPERATION INSPECTION PROCEDURE

STEP INSPECTION RESULTS ACTION
1 While cranking the engine, inspect for fuel injector operation sound at each cylinder using a soundscope.
Is the operation sound heard?
Yes Fuel injector work properly.
No Go to the next step.
2 Disconnect the fuel injector that the operation sound is not heard.
Inspect open or short circuit between suspect fuel injector terminal B (wiring harness-side) and fuel pump relay terminal C (wiring harness-side).
Is there any malfunction?
Yes Repair or replace the wiring harness for a possible open or short circuit.
No Go to the next step.
3 Inspect for open or short circuit between the following terminals (wiring harness-side):
  • Fuel injector No. 1 terminal A-PCM terminal 2BB
  • Fuel injector No. 2 terminal A-PCM terminal 2BC
  • Fuel injector No. 3 terminal A-PCM terminal 2BD
  • Fuel injector No. 4 terminal A-PCM terminal 2AZ

Is there any malfunction?
Yes Repair or replace the wiring harness for a possible open or short circuit.
No Go to the next step.
4 Inspect the suspected fuel injector.
(See FUEL INJECTOR INSPECTION .)
Is there any malfunction?
Yes Replace the suspected fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
No Replace the PCM.
(See PCM REMOVAL/INSTALLATION .)