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Home >> Mazda >> 2012 >> 2 Touring, 1.5L Eng VIN Y, Standard Trans >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting [Engine Control System MZR 1.5] >> Engine Control System Operation Inspection >> Fuel Injector Operation Inspection
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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.
(See ON-BOARD DIAGNOSTIC TEST .)
Turn the fuel injector from on to off using the PIDs for each cylinder.
Does the engine speed drop?		 Yes Fuel injector works properly.
No Go to the next step.
2 Disconnect the fuel injector connector that the engine speed does not drop at Step 1.
Switch the ignition to ON.
Measure the voltage at the suspected fuel injector terminal A (wiring harness-side).
Is the voltage B+  ?		 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open or short circuit.
3 Inspect for open or short circuit between the following terminals (wiring harness-side):
  • Fuel injector No. 1 terminal B-PCM terminal 2A
  • Fuel injector No. 2 terminal B-PCM terminal 2B
  • Fuel injector No. 3 terminal B-PCM terminal 2C
  • Fuel injector No. 4 terminal B-PCM terminal 2H

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 suspect fuel injector.
(See FUEL INJECTOR INSPECTION .)
Is there any malfunction?		 Yes Replace the 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 Inspect for fuel injector operation sound at each cylinder using a soundscope while cranking the engine.
Is the operation sound heard?		 Yes Fuel injector works properly.
No Go to the next step.
2 Disconnect the fuel injector connector that the fuel injector operation sound is not heard at Step 1.
Switch the ignition to ON.
Measure the voltage at the suspected fuel injector terminal A (wiring harness-side).
Is the voltage B+  ?		 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open or short circuit.
3 Inspect for open or short circuit between the following terminals (wiring harness-side):
  • Fuel injector No. 1 terminal B-PCM terminal 2A
  • Fuel injector No. 2 terminal B-PCM terminal 2B
  • Fuel injector No. 3 terminal B-PCM terminal 2C
  • Fuel injector No. 4 terminal B-PCM terminal 2H

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 suspect fuel injector.
(See FUEL INJECTOR INSPECTION .)
Is there any malfunction?		 Yes Replace the fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
No Replace the PCM.
(See PCM REMOVAL/INSTALLATION .)
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