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Home >> Lincoln >> 2004 >> Town Car Protection Series >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test DK: Accelerator Pedal Position Sensor Through Pinpoint Test DV: Throttle Body Assembly Etc - CNG, Flex-Fuel & Gasoline >> Pinpoint Test DK: Accelerator Pedal Position Sensor >> Test Procedure
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Test Procedure

NOTE: Proceed to DTC testing steps listed in FAULT CODE SETTING CONDITION  table of fault code setting condition.
FAULT CODE SETTING CONDITION

Fault Code KOEO KOER Continuous Memory
P2121  DK1  DK1  DK1
P2122  DK1  DK1  DK1
P2123  DK1  DK1  DK1
P2126  DK1  DK1  DK1
P2127  DK1  DK1  DK1
P2128  DK1  DK1  DK1
P2131  DK1  DK1  DK1
P2132  DK1  DK1  DK1
P2133  DK1  DK1  DK1
  1. DK1 DTCS P2121, P2122, P2123, P2126, P2127, P2128, P2131, P2132 AND P2133: CHECK THE APPS FOR OBSTRUCTION 
    • Key in ON position.
    • Press the accelerator pedal fully to the floor and release.

    Does the pedal move freely to the floor and back? 

    Yes No
    For DTC P2111 or P2112, GO to  DV1.
    For all others, GO to  DK2.    		 ISOLATE and REPAIR the obstruction.
  2. DK2 CHECK THE APPS SIGNAL VOLTAGE RANGES FOR THE ACCELERATOR PEDAL FULLY APPLIED AND RELEASED POSITIONS APPS 
    • Access the PCM and monitor the APPS1, APPS2 and APPS3 PIDs.
    • Press the accelerator pedal fully to the floor and release.
    ACCELERATOR PEDAL FULLY APPLIED VOLTAGE VALUES

    VEHICLE APPS1 APPS2 APPS3
    LS 0.50 - 1.44 3.15 - 4.60 2.66 - 3.99
    Thunderbird 0.50 - 1.44 3.15 - 4.60 2.66 - 3.99
    Explorer 0.60 - 1.57 3.07 - 4.50 2.57 - 3.89
    Mountaineer 0.60 - 1.57 3.07 - 4.50 2.57 - 3.89
    F-150 0.60 - 1.57 3.07 - 4.50 2.57 - 3.89
    All others 0.48 - 1.76 2.95 - 4.62 2.43 - 4.02
    ACCELERATOR PEDAL FULLY RELEASED VOLTAGE VALUES

    VEHICLE APPS1 APPS2 APPS3
    All vehicles 3.43 - 4.69 1.13 - 1.88 0.64 - 1.28

    Are all 3 APPS signals out of range for the pedal fully applied and released positions? 

    Yes No
    GO to  DK3. For DTCs P2121, P2122, P2123, P2126, P2127,
    P2128, P2131, P2132 or P2133 alone, GO to  DK7.
    For any combination of ETC related DTCs, GO to  DK3.
    For continuous memory DTCs P2121 and P2126 with P2131, GO to  DK21.
  3. DK3 CHECK THE VREF VOLTAGE TO APPS 
    • Key in OFF position.
    • APP Sensor connector disconnected.
    • Key in ON position.
    • Measure the voltage between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    ETCREF1 - Pin 7 ETCRTN1 - Pin 3
    ETCREF2 - Pin 6 ETCRTN2 - Pin 1

    Are the voltages between 4 V - 6 V? 

    Yes No
    GO to  DK4. GO to PINPOINT TEST C step 1 .
  4. DK4 CHECK THE FUNCTIONALITY OF THE APPS1 CIRCUIT 
    NOTE: Use the voltage measurements from DK2.

    Was APPS1 out of range? 

    Yes No
    GO to  DK7. GO to  DK5.
  5. DK5 CHECK THE FUNCTIONALITY OF APPS2 
    NOTE: Use the voltage measurements from DK2.

    Was APPS2 out of range? 

    Yes No
    GO to  DK7. GO to  DK6.
  6. DK6 CHECK THE FUNCTIONALITY OF APPS3 
    NOTE: Use the voltage measurements from DK2.

    Was APPS3 out of range? 

    Yes No
    GO to  DK7. GO to  DK21.
  7. DK7 CHECK THE FUNCTIONALITY OF APPS 
    • Key in OFF position.
    • APP Sensor connector disconnected.
    • Measure resistance through sensor.
      • APPS1 to ETCRTN1 = 900 - 2,200 ohms.
      • APPS1 to ETCREF1 = 400 - 1,200 ohms.
      • APPS1 to ETCRTN2 = 900 - 2,200 ohms.
      • APPS1 to ETCREF2 = 400 - 1,200 ohms.
      • APPS1 to APPS2 = 2,000 - 4,800 ohms.
      • APPS1 to APPS3 = 2,000 - 4,800 ohms.
      • APPS2 to ETCRTN1 = 1,400 - 3,500 ohms.
      • APPS2 to ETCREF1 = 1,700 - 4,100 ohms.
      • APPS2 to ETCRTN2 = 1,400 - 3,500 ohms.
      • APPS2 to ETCREF2 = 1,700 - 4,100 ohms.
      • APPS2 to APPS3 = 2,700 - 6,500 ohms.
      • APPS3 to ETCRTN1 = 1,300 - 3,200 ohms.
      • APPS3 to ETCREF1 = 1,700 - 4,100 ohms.
      • APPS3 to ETCRTN2 = 1,300 - 3,200 ohms.
      • APPS3 to ETCREF2 = 1,700 - 4,100 ohms.
      • ETCREF1 to ETCRTN1 = 700 - 1,700 ohms.
      • ETCREF1 to ETCRTN2 = 700 - 1,700 ohms.
      • ETCREF2 to ETCRTN1 = 700 - 1,700 ohms.
      • ETCREF2 to ETCRTN2 = 700 - 1,700 ohms.

    Are all the resistances within specifications? 

    Yes No
    For DTCs P2121, P2122 or P2123 alone or in combination, GO to  DK9.
    For DTCs P2126, P2127 or P2128 alone or in combination, GO to  DK13.
    For DTCs P2131, P2132 or P2133 alone or in combination, GO to  DK17.
    For all others, GO to  DK21.    		 INSTALL a new APP sensor.
    Key in ON position.
    Clear the DTCs.
    PRESS the accelerator pedal several times and REPEAT the self-test.
    If DTCs are present:
    GO to  DK8.
  8. DK8 CHECK THE APPS CIRCUIT INTEGRITY 
    • Key in OFF position.
    • APP Sensor connector disconnected.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Component Side ( - ) APP Sensor Connector, Component Side
    ETCREF1 - Pin 7 ETCRTN1 - Pin 3

    Is the resistance between 700 ohms - 1.7K ohms? 

    Yes No
    For continuous memory DTCs P2121 with P2122 or P2123, or with P2126 and P2131, GO to  DK9.
    For continuous memory DTCs P2126 with P2127 or P2128, or with P2121 and P2131, GO to  DK13.
    For continuous memory DTCs P2121 and P2122 or P2131 and P2133, GO to  DK17.    		 INSTALL a new APP sensor.
    KOEO.
    Clear the DTCs.
    PRESS the accelerator pedal several times and REPEAT the self-test.
    If DTCs are present:
    GO to  DK9.
  9. DK9 CHECK THE APPS1 CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side
    APPS1 - Pin 2 APPS1

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DK10. REPAIR the open circuit.
  10. DK10 CHECK THE APPS1 CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    APPS1 - Pin 2 Negative terminal

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  DK11. REPAIR the short circuit to GND.
  11. DK11 CHECK THE APPS1 CIRCUIT FOR A SHORT IN THE HARNESS 
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    APPS1 - Pin 2 ETCRTN1 - Pin 3
    APPS1 - Pin 2 ETCRTN2 - Pin 1
    APPS1 - Pin 2 ETCREF1 - Pin 7
    APPS1 - Pin 2 ETCREF2 - Pin 6

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DK12. REPAIR the short circuit.
  12. DK12 CHECK THE APPS1 CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in ON position.
    • Measure the voltage between:
    ( + ) APP Sensor Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    APPS1 - Pin 2 Negative terminal

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. GO to  DK21.
  13. DK13 CHECK THE APPS2 CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side
    APPS2 - Pin 5 APPS2

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DK14. REPAIR the open circuit.
  14. DK14 CHECK THE APPS2 CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    APPS2 Negative terminal

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  DK15. REPAIR the short circuit to GND.
  15. DK15 CHECK THE APPS2 CIRCUIT FOR A SHORT IN THE HARNESS 
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    APPS2 - Pin 5 ETCRTN1 - Pin 3
    APPS2 - Pin 5 ETCRTN2 - Pin 1
    APPS2 - Pin 5 ETCREF1 - Pin 7
    APPS2 - Pin 5 ETCREF2 - Pin 6

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DK16. REPAIR the short circuit.
  16. DK16 CHECK THE APPS2 CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in ON position.
    • Measure the voltage between:
    ( + ) PCM Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    APPS2 Negative terminal

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. GO to  DK22.
  17. DK17 CHECK THE APPS3 CIRCUIT FOR AN OPEN IN THE HARNESS 
    • PCM connector disconnected.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side
    APPS3 - Pin 8 APPS3

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  DK18. REPAIR the open circuit.
  18. DK18 CHECK THE APPS3 CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • Measure the resistance between:
    ( + ) PCM Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    APPS3 Negative terminal

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  DK19. REPAIR the short circuit to GND.
  19. DK19 CHECK THE APPS3 CIRCUIT FOR A SHORT IN THE HARNESS 
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    APPS3 - Pin 8 ETCRTN1 - Pin 3
    APPS3 - Pin 8 ETCRTN2 - Pin 1
    APPS3 - Pin 8 ETCREF1 - Pin 7
    APPS3 - Pin 8 ETCREF2 - Pin 6

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DK20. REPAIR the short circuit.
  20. DK20 CHECK THE APPS3 CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key in ON position.
    • Measure the voltage between:
    ( + ) PCM Connector, Harness Side ( - ) 12 Volt Vehicle Battery
    APPS3 Negative terminal

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. GO to  DK23.
  21. DK21 CHECK THE APPS1 CIRCUIT FOR A SHORT TOGETHER 
    • Key in OFF position.
    • PCM connector disconnected.
    • APP Sensor connector disconnected.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    APPS1 - Pin 2 APPS2 - Pin 5
    APPS1 - Pin 2 APPS3 - Pin 8
    APPS1 - Pin 2 ETCRTN1 - Pin 3
    APPS1 - Pin 2 ETCRTN2 - Pin 1
    APPS1 - Pin 2 ETCREF1 - Pin 7
    APPS1 - Pin 2 ETCREF2 - Pin 6

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DK22. REPAIR the short circuit.
  22. DK22 CHECK FOR THE APPS2 CIRCUIT SHORTED TO SIGNALS IN THE SAME HARNESS 
    • Key in OFF position.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    APPS2 - Pin 5 APPS1 - Pin 2
    APPS2 - Pin 5 APPS3 - Pin 8
    APPS2 - Pin 5 ETCRTN1 - Pin 3
    APPS2 - Pin 5 ETCRTN2 - Pin 1
    APPS2 - Pin 5 ETCREF1 - Pin 7
    APPS2 - Pin 5 ETCREF2 - Pin 6

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DK23. REPAIR the short circuit.
  23. DK23 CHECK FOR THE APPS3 CIRCUIT SHORTED TO SIGNALS IN THE SAME HARNESS 
    • Key in OFF position.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) APP Sensor Connector, Harness Side
    APPS3 - Pin 8 APPS1 - Pin 2
    APPS3 - Pin 8 APPS2 - Pin 5
    APPS3 - Pin 8 ETCRTN1 - Pin 3
    APPS3 - Pin 8 ETCRTN2 - Pin 1
    APPS3 - Pin 8 ETCREF1 - Pin 7
    APPS3 - Pin 8 ETCREF2 - Pin 6

    Are the resistances greater than 10K ohms? 

    Yes No
    GO to  DK24. REPAIR the short circuit.
  24. DK24 CHECK THE APPS CIRCUIT FOR AN INTERMITTENT CONCERN 
    • Wiggle, shake, and bend small sections of the wiring harness while working from the sensor to the PCM.
    • Measure the resistance between:
    ( + ) APP Sensor Connector, Harness Side ( - ) PCM Connector, Harness Side
    APPS1 - Pin 2 APPS1
    APPS2 - Pin 5 APPS2
    APPS3 - Pin 8 APPS3

    Are the resistances less than 5 ohms? 

    Yes No
    INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . ISOLATE the fault and REPAIR as necessary.
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