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Fuel Injector Operation Inspection

If simulation function of M-MDS is used:

FUEL INJECTOR OPERATION INSPECTION

STEP	INSPECTION		ACTION
1	Start the engine and warm it up until normal operating temperature. Connect the M-MDS to DLC-2. Select the INJ#1, INJ#2, INJ#3, and INJ#4 PIDs. Turn the fuel injector from on to off using the PIDs for each cylinder. Does the engine speed drop?	Yes	Fuel injector work properly
1		No	Engine speed does not drop an any cylinder: Go to the next steps. Engine speed drops on some cylinders: Go to step 3.
2	Perform the Main Relay Operation Inspection. (See MAIN RELAY OPERATION INSPECTION ). Does the main relay work properly?	Yes	Go to the next step.
2		No	Repair or replace the malfunctioning parts.
3	Inspect the fuel injector of the suspected cylinder. (See FUEL INJECTOR INSPECTION ). Is the fuel injector normal?	Yes	Inspect the following for the suspected cylinder. Fuel injector power and/or ground systems related wiring harness and connectors. If all items normal replace the injector driver module. (See INJECTOR DRIVER MODULE REMOVAL/INSTALLATION ).
3		No	Replace the fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION ).
4	Perform KOER self-test function using the M-MDS. (See KOEO/KOER SELF TEST ). Are DTCs P0201, P0202, P0203 and/or P0204 present?	Yes	Go to the appropriate DTC test. (See DTC TABLE ).
4		No	Go to the next step.
5	Inspect the fuel injector of the suspected cylinder. (See FUEL INJECTOR INSPECTION ). Is the fuel injector normal?	Yes	Inspect the following for the suspected cylinder: PCM terminals (pulled-out pins, corrosion) Injector driver module terminals (pulled-out pins, corrosion) Fuel injector terminals (pulled-out pins, corrosion) If all items are normal replace the injector driver module. (See INJECTOR DRIVER MODULE REMOVAL/INSTALLATION ).
5		No	Replace the fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION ).

If simulation function of M-MDS is not used:

FUEL INJECTOR OPERATION INSPECTION

STEP	INSPECTION		ACTION
1	Perform the KOER self-test function using the M-MDS. (See (0102) KOEO/KOER SELF-TEST). Are DTCs P0201, P0202, P0203 and/or P0204 present?	Yes	Go to appropriate DTC test. (See DTC TABLE ).
1		No	Go to the next step.
2	Inspect the fuel injector for each cylinder. (See FUEL INJECTOR INSPECTION ). Is the fuel injector normal?	Yes	Go to the next step.
2		No	Replace the fuel injector. (See FUEL INJECTOR REMOVAL/INSTALLATION ).
3	Inspect the following for the suspected cylinder: Fuel injector power and/or ground system related wiring harnesses and connectors. PCM terminals (pulled-out pins, corrosion) Injector driver module terminals (pulled-out pins, corrosion) Fuel injector terminals (pulled-out pins, corrosion) Are all items normal?	Yes	Replace the injector driver module. (See INJECTOR DRIVER MODULE REMOVAL/INSTALLATION ).
3		No	Repair or replace malfunctioning parts.