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Home >> Ford >> 2004 >> Focus LX, 2.0 P, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test QB: DTCS P0603 Or P1633: Keep Alive Power Through Pinpoint Test Z: Intermittent - CNG, Flex-Fuel & Gasoline >> Pinpoint Test TB: Transmission Control Switch TCS/Transmission Control Indicator Lamp TCIL >> Test Procedure
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Test Procedure

  1. TB1 DTC P1780: CHECK THE TCS FUNCTION 
    • Key ON Engine OFF.
    • Access the TCS PID.
    • Cycle the TCS.

    Does the TCS PID change state? 

    Yes No
    KEY OFF
    RERUN KOER Self-Test and cycle TCS during test.    		 For Freestar, refer to AUTOMATIC TRANSAXLE/TRANSMISSION .
    All others:
    GO to  TB2.
  2. TB2 CHECK TCS VOLTAGE 
    • PCM connector disconnected.
    • Key ON Engine OFF.
    • Measure the voltage between:
    ( + ) PCM Connector, Harness Side ( - )
    TCS Ground
    • Monitor the voltage while cycling the TCS several times.

    Did the voltage cycle? 

    Yes No
    KEY OFF
    REPLACE the PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM .    		 GO to  TB3.
  3. TB3 CHECK THE TCS CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS 
    • TCS connector disconnected.
    • Measure the resistance between:
    ( + )PCM Connector, Harness Side ( - )
    TCS Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to  TB4. REPAIR the short circuit.
  4. TB4 CHECK THE TCS CIRCUIT FOR VOLTAGE 
    • Key ON Engine OFF.
    • Measure the voltage between:
    ( + )TCS Connector, Harness Side ( - )Vehicle battery
    IGN START/RUN Negative terminal

    Is the voltage greater than 10.5 V? 

    Yes No
    GO to  TB5. REPAIR the open circuit.
  5. TB5 CHECK THE TCS CIRCUIT FOR AN OPEN IN THE HARNESS 
    • Key OFF.
    • Measure the resistance between:
    ( + )PCM Connector, Harness Side ( - )TCS Connector, Harness Side
    TCS TCS

    Is the resistance less than 5 ohms? 

    Yes No
    GO to  TB6. REPAIR the open circuit.
  6. TB6 CHECK THE TCS CIRCUIT FOR A SHORT TO POWER IN THE HARNESS 
    • Key ON Engine OFF.
    • Measure the voltage between:
    ( + )TCS Connector, Harness Side ( - )Vehicle battery
    TCS Negative terminal

    Is the voltage less than 1 V? 

    Yes No
    REPLACE the TCS. REPAIR the short circuit.
  7. TB7 CHECK TCIL FUNCTION - TCIL ALWAYS ON 
    • Key ON Engine OFF.
    • Cycle the TCS.

    Did the TCIL change state? 

    Yes No
    Perform intermittent fault testing
    GO to  Z1.    		 GO to  TB8
  8. TB8 CHECK THE TCIL CIRCUIT(S) FOR A SHORT TO GROUND IN THE HARNESS 
    • Key OFF.
    • PCM connector disconnected.
    • Key ON Engine OFF.
    NOTE: TCIL turns off when the PCM is disconnected.

    Did the TCIL change state? 

    Yes No
    REPLACE the PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . REPAIR the short circuit
    VERIFY a symptom no longer exists.
  9. TB9 CHECK FOR DTCS - TCIL NEVER ON 
    • CHECK PCM KOER DTCs:

    Is DTC P1780 present? 

    Yes No
    REPAIR DTC
    GO to  TB1.    		 GO to  TB10.
  10. TB10 CHECK FOR VOLTAGE TO TCIL 
    • Key OFF.
    • PCM connector disconnected.
    • Key ON Engine OFF.
    • Connect a 5 amp fused jumper wire between the following:
    Point A PCM Connector, Harness Side Point B Vehicle battery
    TCIL Negative terminal

    Did the TCIL illuminate? 

    Yes No
    REPLACE the PCM. REFER to FLASH ELECTRICALLY ERASEABLE PROGRAMMABLE READ ONLY MEMORY - FLASH EEPROM . CHECK the indicator bulb and fuse
    If OK, open is in wiring between the ignition switch and TCIL pin at PCM harness connector.
    CYCLE TCS to check operation of TCIL. REPAIR as necessary.
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