2014 Mazda 3 SV, Standard TransFACTORY OEM SERVICE PROCEDURE

Fuel Injector Operation Inspection

M-MDS SIMULATION FUNCTION DESCRIPTION

STEP INSPECTION ACTION
1 Start the engine and warm it up completely. Access the INJ_1, INJ_2, INJ_3 and INJ_4 PIDs using the M-MDS.
(See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
Turn each fuel injector from on to off using the PIDs for each cylinder.
Does the engine speed drop?		 Yes Fuel injectors work properly.
No Engine speed does not drop an any cylinder:
  • Go to the next step.

Engine speed drops on some cylinders:
  • Go to Step 4.
2 Perform the Main Relay Operation Inspection. (Seed-03-148 Main Relay Operation Inspection.)
Does the main relay work properly?		 Yes Go to the next step.
No Repair or replace the malfunctioning part according to the inspection results.
3 Inspect the fuel injector of the suspected cylinder.
(See FUEL INJECTOR INSPECTION .) Is there any malfunction?		 Yes Replace the fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
No Inspect the fuel injector power and/or ground systems related wiring harness and connectors for the suspected cylinder.
  • If all items normal:
  • If not:
    • Repair or replace the malfunctioning part according to the inspection results.
4 Perform the KOER self test using the M-MDS. (See KOEO/KOER SELF TEST [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .) Are the DTCs P0201:00, P0202:00, P0203:00 and/or P0204:00 present? Yes Go to the appropriate DTC inspection.
(See DTC P0201:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
(See DTC P0202:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
(See DTC P0203:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
(See DTC P0204:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
5 Inspect the fuel injector of the suspected cylinder.
(See FUEL INJECTOR INSPECTION .) Is there any malfunction?		 Yes Replace the fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
No Inspect the following for the suspected cylinder:
  • PCM terminals (pulled-out pins, corrosion)
  • Fuel injector terminals (pulled-out pins, corrosion)
  • If all items normal:
  • If not:
    • Repair or replace the malfunctioning part according to the inspection results.
M-MDS SIMULATION FUNCTION DESCRIPTION

STEP INSPECTION ACTION
1 Perform the KOER self test using the M-MDS. (See KOEO/KOER SELF TEST [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
Are the DTCs P0201:00, P0202:00, P0203:00 and/or P0204:00 present?		 Yes Go to the appropriate DTC inspection.
(See DTC P0201:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
(See DTC P0202:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
(See DTC P0203:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
(See DTC P0204:00 [SKYACTIV-G 2.0, SKYACTIV-G 2.5] .)
No Go to the next step.
2 Inspect the fuel injector of the suspected cylinder.
(See FUEL INJECTOR INSPECTION .) Is there any malfunction?		 Yes Replace the fuel injector.
(See FUEL INJECTOR REMOVAL/INSTALLATION .)
No Go to the next step.
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)
  • Fuel injector terminals (pulled-out pins, corrosion)

Is there any malfunction?		 Yes Repair or replace the malfunctioning part according to the inspection results.
No Replace the PCM.
(See PCM REMOVAL/INSTALLATION .)
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.