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Home >> Ford >> 2005 >> Escape Base, 2.3 Z, FWD, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test Hg: Positive Crankcase Ventilation (PCV) System Through Pinpoint Test JD: Crankshaft Position (CKP) Sensor - (Except Diesel & Hybrid) >> Pinpoint Test HY: Generator/Regulator System >> Test Procedure
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Test Procedure

  1. HY1 DTCS P0620, P0622, P1244, P1245, P1246: VISUAL INSPECTION 
    • Check that the output cable is clean at the generator/regulator assembly.
    • Check that the output cable nut and battery sense line is tightened at the generator/regulator assembly.
    • Check the generator drive belt condition.
    • Start the engine, and verify generator is turning.

    Are there any concerns found during the visual inspection? 

    Yes No
    REPAIR as necessary. Key in OFF position.
    GO to  HY2.
  2. HY2 CHECK THE GENERATOR CHARGING VOLTAGE 
    • All accessories OFF (no load on engine).
    • Key on engine running.
    • Make sure that the engine is idling.
    • Connect a voltmeter across the battery terminals.
    • Accelerate the engine speed to 2, 000 RPM and observe the voltage reading across the battery terminals.

    Is the battery voltage between 13 and 16 volts? 

    Yes No
    GO to  HY4. GO to  HY3.
  3. HY3 CHECK GENERATOR OUTPUT TO THE BATTERY 
    • Make sure that the engine is idling.
    • Measure the voltage between the generator output cable and the generator outer shell (for ground) at the generator/regulator assembly.

    Is the voltage reading between 12.5 and 15 volts? 

    Yes No
    Key in OFF position. GO to  HY4. Key in OFF position. REPAIR the open circuit.
  4. HY4 CHECK THE BATTERY SENSE VOLTAGE AT THE BATTERY 
    • Battery output cable at generator/regulator assembly connected.
    • The battery terminals are connected.
    • Disconnect the generator/regulator harness connector.
    • Key in ON position.
    • Measure the battery sense voltage from the B+ pin at the generator harness connector and GND.

    Is the battery sense voltage within plus or minus 0.5 volt of the battery voltage? 

    Yes No
    Key in OFF position.
    For Aviator,
    Explorer, and
    Mountaineer, GO to  HY5.
    For LS, and
    Thunderbird, GO to  HY5.
    For all others, GO to  HY6.    		 Key in OFF position. REPAIR the open circuit.
  5. HY5 CHECK THE GENLI AND ILC CIRCUITS FOR A SHORT TO PWR 
    NOTE: The voltage measurements in this test step are to be taken between the PCM signal harness pin and chassis ground. LS and Thunderbird have GENLI and ILC circuits. Aviator, Explorer/Mountaineer only has a GENLI circuit.
    • Disconnect the generator/regulator harness connector.
    • PCM connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
      (+) GEN Assembly Connector, Harness Side (-)
      GENLI Ground
      ILC Ground

    Are the voltages less than 0.5 V? 

    Yes No
    Key in OFF position. GO to  HY9. Key in OFF position. REPAIR the short circuit to PWR.
  6. HY6 CHECK FOR GENRC CIRCUIT FAULT IN THE GENERATOR 
    • Key in OFF position.
    • Measure the resistance between:
      (+) GEN Assembly Connector, Harness Side (-) GEN Assembly Connector, Harness Side
      GENRC B+

    Is the resistance between 900 ohms - 1.2K ohms? 

    Yes No
    GO to  HY7. INSTALL a new Generator.
  7. HY7 CHECK FOR GENRC CIRCUIT FAULT IN THE GENERATOR 
    • Measure the resistance between:
      (+) GEN Assembly Connector, Harness Side (-)
      GENRC Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  HY8. INSTALL a new Generator.
  8. HY8 CHECK THE GENLI AND GENRC CIRCUITS FOR A SHORT TO PWR 
    NOTE: The voltage measurements in this test step are to be taken between the PCM signal harness pin and chassis ground.
    • Disconnect the generator/regulator harness connector.
    • Disconnect the PCM.
    • Key in ON position.
    • Measure the voltage between:
      (+) GEN Assembly Connector, Harness Side (-)
      GENLI Ground
      GENRC Ground

    Are the voltages less than 1 V? 

    Yes No
    Key in OFF position.
    GO to  HY10.    		 Key in OFF position. REPAIR the short circuit to PWR.
  9. HY9 CHECK THE GENLI AND ILC CIRCUITS FOR A SHORT TO GND 
    NOTE: The resistance measurements in this test step are to be taken between the PCM signal harness pin and chassis ground. LS and Thunderbird have GENLI and ILC circuits. Aviator, Explorer/Mountaineer only has a GENLI circuit.
    • Measure the resistance between:
      (+) GEN Assembly Connector, Harness Side (-)
      GENLI Ground
      ILC Ground

    Are the resistances greater than 10K ohms? 

    Yes No
    For LS, and
    Thunderbird, GO to  HY15.
    For Aviator,
    Explorer, and
    Mountaineer, GO to  HY13.    		 REPAIR the short circuit to GND.
  10. HY10 CHECK THE GENLI AND GENRC CIRCUITS FOR A SHORT TO GND 
    NOTE: The resistance measurements in this test step are to be taken between the PCM signal harness pin and chassis ground.
    • Measure the resistance between:
      (+) GEN Assembly Connector, Harness Side (-)
      GENLI Ground
      GENRC Ground

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  HY11. REPAIR the short circuit to GND.
  11. HY11 CHECK GENLI CIRCUIT SHORT TO GENRC CIRCUIT IN THE HARNESS 
    • Measure the resistance between:
      (+) GEN Assembly Connector, Harness Side (-) GEN Assembly Connector, Harness Side
      GENLI GENRC

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  HY12. REPAIR the short circuit.
  12. HY12 CHECK THE GENLI AND GENRC CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
      (+) GEN Assembly Connector, Harness Side (-) PCM Connector, Harness Side
      GENLI GENLI
      GENRC GENRC

    Are the resistances less than 5 ohms? 

    Yes No
    GO to  HY14. REPAIR the open circuit.
  13. HY13 CHECK THE ILC CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) GEN Assembly Connector, Harness Side
      ILC ILC

    Is the resistance less than 5 ohms? 

    Yes No
    REFER to CHARGING SYSTEM - GENERAL INFORMATION and diagnose the charging system by symptom. REPAIR the open circuit.
  14. HY14 CHECK THE GENERATOR MONITOR SIGNAL 
    • PCM connector connected.
    • Reconnect the generator/regulator harness connector.
    • Key on engine running.
    • Make sure that the engine is idling.
    • Access the PCM and monitor the GFS PID.

    Is the duty cycle between 5% - 97%? 

    Yes No
    Key in OFF position.
    The fault is no longer present. The fault could not be isolated.
    GO to PINPOINT TEST Z STEP 1 .    		 Key in OFF position. INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) .
  15. HY15 CHECK THE GENLI AND ILC CIRCUITS FOR AN OPEN IN THE HARNESS 
    NOTE: LS and Thunderbird have GENLI and ILC circuits.
    • Measure the resistance between:
      (+) PCM Connector, Harness Side (-) GEN Assembly Connector, Harness Side
      GENLI GENLI
      ILC ILC

    Are the resistances less than 5 ohms? 

    Yes No
    REFER to CHARGING SYSTEM - GENERAL INFORMATION and diagnose the charging system by symptom. REPAIR the open circuit.
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