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Home >> Ford >> 2006 >> Focus ZX4 S, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test HY: Generator/Regulator System Through Pinpoint Test KD: Electric Exhaust Gas RECIRCULATION (EEGR) System - (Except Diesel & Hybrid) >> Pinpoint Test JB: Secondary Ignition (Cop) >> Test Procedure
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Test Procedure

  1. JB1 CHECK FOR DTCS 

    Are DTCs P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309, P0310, or P050B present? 

    Yes No
    For DTCs P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309 or P0310, GO to  JB3. For symptoms without DTCs, GO to  JB2.
    For DTC P050B, GO to  JB14. For all other DTCs, GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS .
  2. JB2 VISUAL INSPECTION OF THE IGNITION SYSTEM 
    • Visually inspect the engine compartment to make sure all coils are properly and securely connected.
    • Examine all the wiring harnesses and connectors for damaged, burned, or overheated insulation, and loose or broken conditions.
    • Make sure the vehicle battery is in good condition and all of the accessories are turned off.

    Is a concern present? 

    Yes No
    REPAIR as necessary.
    CLEAR the DTCs. REPEAT the self-test.    		 GO to  JB3.
  3. JB3 DTC P0301 THROUGH P0310: MISFIRE ON CYLINDERS 1 THROUGH 10 

    Are DTCs P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0309, or P0310 present? 

    Yes No
    GO to  JB4. GO to  JB7.
  4. JB4 CHECK VEHICLE LINE 

    Is this a Fusion, Milan, Zephyr or Explorer 4.6L? 

    Yes No
    GO to  JB5. GO to  JB6.
  5. JB5 CHECK SPARK DURATION RELATIVENESS 
    • Monitor the spark duration PIDs.

    Are the PIDs relative to each other? 

    Yes No
    GO to  JB11. INSPECT the coil boot(s) for the missing cylinder(s). INSTALL a new coil boot(s) if necessary. INSPECT the spark plug(s) for the missing cylinder(s). MEASURE the resistance of the spark plug(s). INSTALL a new spark plug(s) if the resistance is lower than 2,000 ohms or higher than 20,000 ohms. REFER to the appropriate ENGINE IGNITION article . If the coil boot(s) and spark plugs are OK, INSTALL a new COP(s) for the missing cylinders. CLEAR the DTCs. REPEAT the selftest.
  6. JB6 CHECK FOR SPARK AT THE CYLINDER(S) INDICATED BY THE DTC(S) 
    • Locate and activate the fuel inertia switch to disable the fuel pump.
    • Disconnect the ignition coil(s) from the spark plug(s).
    • Connect the Air Gap spark tester 303-D037 (D81P-6666-A) or its equivalent to the suspect coil.
    • If a worldwide diagnostic system (WDS) or equivalent diagnostic tool is available, use the scope function to verify that the coil is the problem.
    • Observe the spark tester while cranking the engine.

    Is a bluish-white spark present? 

    Yes No
    GO to  JB9. INSPECT the coil boot(s) for the missing cylinder(s). INSTALL a new coil boot(s) if necessary. INSPECT the spark plug(s) for the missing cylinder(s). MEASURE the resistance of the spark plug(s). INSTALL a new spark plug(s) if the resistance is lower than 2,000 ohms or higher than 20,000 ohms. REFER to the appropriate ENGINE IGNITION article .
    GO to  JB8.
  7. JB7 CHECK FOR SPARK AT ALL CYLINDERS 
    • Key in OFF position.
    • Locate and activate the fuel inertia switch to disable the fuel pump.
    • Disconnect the ignition coil(s) from the spark plug(s).
    • Connect the Air Gap spark tester 303-D037 (D81P-6666-A) or its equivalent to the suspect coil.
    • Observe the spark tester at each cylinder while cranking the engine.

    Is a bluish-white spark consistent between all cylinders? 

    Yes No
    GO to  JB9. INSPECT the coil boot(s) for the missing cylinder(s). INSTALL a new coil boot(s) if necessary. INSPECT the spark plug(s) for the missing cylinder(s). MEASURE the resistance of the spark plug(s). INSTALL a new spark plug(s) if the resistance is lower than 2,000 ohms or higher than 20,000 ohms. RECORD the cylinder (s) with inconsistent spark. REFER to the appropriate ENGINE IGNITION article .
    GO to  JB8.
  8. JB8 CHECK THE SECONDARY COIL RESISTANCE FOR THE MISSING CYLINDERS 
    • Key in OFF position.
    • Suspect coil connector disconnected.
    • Measure resistance between: Suspect COP connector, IGN START/RUN, component side and ignition coil spring, located in the ignition coil boot.

    Is the resistance between 5,000 and 6,000 ohms? 

    Yes No
    GO to Pinpoint Test Z . INSTALL a new COP.
    CLEAR the DTCs. REPEAT the self-test.
  9. JB9 CHECK THE SPARK PLUGS 
    • Key in OFF position.
    • Remove and inspect the plugs for damage, wear, carbon deposits, and proper plug gap.

    Are the plugs OK? 

    Yes No
    GO to  JB10. REPAIR the plug(s). ADJUST the gap or INSTALL a new spark plug(s) as necessary. REFER to the appropriate ENGINE IGNITION article .
    CLEAR the DTCs. REPEAT the self-test.
  10. JB10 CHECK THE SPARK PLUG RESISTANCE 
    • Measure the spark plug resistance.

    Is the resistance between 2,000 and 20,000 ohms? 

    Yes No
    For Explorer 4.6L, Fusion, Milan, Zephyr
    GO to  JB15.    		 INSTALL a new spark plug. REFER to the appropriate ENGINE IGNITION article .
    For all others, GO to  JB11. CLEAR the DTCs. REPEAT the self-test.
  11. JB11 TEST DIRECTION FOR SYMPTOM CHARTS 

    Were you directed to this pinpoint test from  SYMPTOM CHARTS  article? 

    Yes No
    The concern is elsewhere. RETURN to SYMPTOM CHARTS for further direction. GO to  JB12.
  12. JB12 TEST DIRECTION FOR PINPOINT TEST HD 

    Were you directed to this pinpoint test from pinpoint test step HD5? 

    Yes No
    GO to PINPOINT TEST HD step 7 . GO to  JB13.
  13. JB13 TEST DIRECTION FOR PINPOINT TEST A 

    Were you directed to this pinpoint test from pinpoint test step A8? 

    Yes No
    GO to PINPOINT TEST A step 9 . The concern is intermittent.
    GO to Pinpoint Test Z .
  14. JB14 DTC P050B: COLD START PERFORMANCE 

    Are any other codes besides P050B present? 

    Yes No
    REPAIR all other powertrain related diagnostic trouble codes (DTCs) first. GO to  JB15.
  15. JB15 CHECK THE SPARK CAPTURE CIRCUIT 
    • Access the PCM and monitor the IGNPCM_F PID.

    Is a fault indicated? 

    Yes No
    GO to  JB17. GO to  JB16.
  16. JB16 CHECK THE IGNITION TIMING PID 
    • Access the PCM and monitor the IGNX_F PIDs.

    Is a concern indicated? 

    Yes No
    Visually inspect the COP harness for damage, exposed wiring, water contamination, corrosion, and correct assembly. REPAIR as necessary.
    CLEAR the DTCs. REPEAT the self-test.    		 GO to  JB17.
  17. JB17 CHECK FOR CORRECT PCM OPERATION 
    • Disconnect all the PCM connectors.
    • Visually inspect for:
      • pushed out pins
      • corrosion
    • Connect all the PCM connectors and make sure they seat correctly.
    • Carry out the PCM self-test and verify the concern is still present.

    Is the concern still present? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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