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Fuel Injector Operation Inspection

If simulation function of M-MDS is used: 

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 [MZR 2.5] .)
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: 

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 .)
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