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Fuel Injector Malfunction

DTC P0201, P0202, P0203, P0204, P0205, P0206 DETECTION CONDITION AND POSSIBLE CAUSE

DTC P0201, P0202, P0203, P0204, P0205, P0206  FUEL INJECTOR MALFUNCTION 
DETECTION CONDITION 
  • P0201-P0206 indicates the fuel injector does not operate electrically even though the harness assembly and fuel injectors test satisfactorily.
POSSIBLE CAUSE 
  • Faulty fuel injector driver within the PCM.
HINT  Fuel Injector Description 
  • Solenoid-operated valve that meters fuel flow to the engine.
    • Opens and closes a constant number of times per crankshaft revolution.
    • The amount of fuel is controlled by the length of time it is held open.
  • Normally closed and is operated by 12 V VPWR from the electronic engine control power relay with the ground controlled by the PCM.
G03988121Courtesy of MAZDA MOTORS CORP.
DTC P0201, P0202, P0203, P0204, P0205, P0206 INSPECTION

STEP INSPECTION ACTION
1 PCM QUICK TEST
  • Was PCM Quick Test performed? 
 Yes Go to next step.
No Perform PCM Quick Test.
2 CHECK INJECTOR FAULT PIDS
  • Access INJ1F-INJ6F PIDs using NGS Tester.
  • Is an injector(s) fault present? 
 Yes Go to next step.
No Go to step 6.
3 CHECK FUEL INJECTOR(S) AND HARNESS RESISTANCE
NOTE: This erases Continuous Memory DTCs.
  • Disconnect PCM.
  • Install Breakout Box, leave PCM disconnected. Note Use the injector fault PID to determine the fuel injector circuit(s) requiring testing.
    NOTE: Use the injector fault PID to determine the fuel injector circuit(s) requiring testing.
  • Measure resistance of fuel injector between suspect INJ circuit PCM test pin and PCM test pin 71 (VPWR).
  • Is the resistance between 11.0-18.0 ohms? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Go to step 6.
No Go to next step.
4 CHECK FUEL INJECTOR HARNESS RESISTANCE
  • Disconnect fuel injector harness connector at the suspect fuel injector.
  • Measure resistance of VPWR circuit between PCM test pin 71 and the fuel injector harness connector.
  • Measure resistance of INJ circuit between appropriate PCM test pin and the fuel injector harness connector.
  • Is each resistance less than 5.0 ohms? 
 Yes Go to next step.
No Repair open harness circuit.
Go to step 6.
5 CHECK FUEL INJECTOR HARNESS CIRCUIT FOR SHORT TO POWER AND GROUND
  • Measure resistance between suspect INJ circuit PCM test pin and PCM test pin 71 (VPWR).
  • Measure resistance between suspect INJ circuit PCM test pin and PCM test pin 103 (PWR GND).
  • Is each resistance greater than 10K ohms? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Repeat PCM Quick Test.
Go to step 6.
No Repair short circuit.
Go to step 6.
6 VERIFY TROUBLESHOOTING OF DTCs COMPLETED
  • Make sure to reconnect all disconnected connectors.
  • Clear DTCs from PCM memory using NGS tester generic OBD-II function.
  • Perform PCM Quick Test.
  • Is same DTC present? 
 Yes Replace PCM. See COMPUTERIZED ENGINE CONTROLS .
Repeat PCM Quick Test.
No If any other DTC is present, go to applicable DTC inspection.
If no DTC is present, troubleshooting complete.
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