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Home >> Ford >> 2013 >> Focus S, Automatic DCT Trans, Gas/Ethanol >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Pinpoint Test Do: Barometric Pressure (BARO) Sensor Through Pinpoint Test FB: Power Take Off (PTO) - (Except Diesel & Hybrid) >> Pinpoint Test FA: Ambient Air Temperature (AAT) Sensor >> Test Procedure
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Test Procedure

  1. FA1 CHECK FOR DTCS 

    Are DTCs P0071, P0072, P0073 or P0074 present? 

    Yes No
    For DTC P0071, GO to  FA8.
    For DTC P0072, GO to FA2  .
    For DTC P0073, GO to  FA3.
    For DTC P0074, GO to  FA7.    		 For all others, GO to DIAGNOSTIC TROUBLE CODE (DTC) CHARTS AND DESCRIPTIONS .
  2. FA2 INDUCING THE OPPOSITE DTC 
    NOTE: The AAT sensor is disconnected to simulate the opposite DTC.
    • Ignition OFF.
    • For Focus,
    • Right Exterior Rear View Mirror Assembly connector disconnected.
    • For all others,
    • AAT Sensor connector disconnected.
    • Ignition ON, engine OFF.
    • Carry out the PCM self-test.

    Is the DTC P0073 present? 

    Yes No
    For Focus, INSTALL a new Right Exterior Rear View Mirror. REFER to the appropriate Rear View Mirrors article.
    For all others, INSTALL a new AAT sensor. REFER to the appropriate Climate Control article.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to  FA4.
  3. FA3 INDUCING THE OPPOSITE DTC 
    NOTE: DTCs set as a result of the connector being disconnected.
    • Ignition OFF.
    • For Focus,
    • Right Exterior Rear View Mirror Assembly connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A Right Exterior Rear View Mirror Assembly Connector, Harness Side Point B Right Exterior Rear View Mirror Assembly Connector, Harness Side
      AAT - Pin 9 SIGRTN - Pin 10
    • For all others,
    • AAT Sensor connector disconnected.
    • Connect a 5 amp fused jumper wire between the following:
      Point A AAT Sensor Connector, Harness Side Point B AAT Sensor Connector, Harness Side
      AAT SIGRTN
    • Ignition ON, engine OFF.
    • Carry out the on-demand self-test.

    Is DTC P0072 present? 

    Yes No
    For Focus, INSTALL a new Right Exterior Rear View Mirror. REFER to the appropriate Rear View Mirrors article.
    For all others, INSTALL a new AAT sensor. REFER to the appropriate Climate Control article.
    Clear the PCM DTCs. REPEAT the self-test.    		 GO to FA4  .
  4. FA4 CHECK THE AAT AND SIGRTN CIRCUITS FOR AN OPEN 
    • Ignition OFF.
    • For Fiesta,
    • IPC connector disconnected.
    • Measure the resistance between:
      (+) AAT Sensor Connector, Harness Side (-) IPC Connector, Harness Side
      AAT AAT - Pin 20
      SIGRTN SIGRTN - Pin 19
    • For Focus,
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) Right Exterior Rear View Mirror Assembly Connector, Harness Side (-) PCM Connector, Harness Side
      AAT - Pin 9 AAT
      SIGRTN - Pin 10 SIGRTN
    • For all others,
    • PCM connector disconnected.
    • Measure the resistance between:
      (+) AAT Sensor Connector, Harness Side (-) PCM Connector, Harness Side
      AAT AAT
      SIGRTN SIGRTN

    Are the resistances less than 5 ohms? 

    Yes No
    GO to FA5  . REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test.
  5. FA5 CHECK THE AAT CIRCUIT FOR A SHORT TO GROUND 
    • For Focus,
    • Measure the resistance between:
      (+) Right Exterior Rear View Mirror Assembly Connector, Harness Side (-)
      AAT - Pin 9 Ground
    • For all others,
    • Measure the resistance between:
      (+) AAT Sensor Connector, Harness Side (-)
      AAT Ground

    Is the resistance greater than 10K ohms? 

    Yes No
    GO to FA6  . REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test.
  6. FA6 CHECK THE AAT AND SIGRTN CIRCUITS FOR A SHORT TO VOLTAGE 
    • Ignition ON, engine OFF.
    • For Focus,
    • Measure the voltage between:
      (+) Right Exterior Rear View Mirror Assembly Connector, Harness Side (-)
      AAT - Pin 9 Ground
      SIGRTN - Pin 10 Ground
    • For all others,
    • Measure the voltage between:
      (+) AAT Sensor Connector, Harness Side (-)
      AAT Ground
      SIGRTN Ground

    Is any voltage present? 

    Yes No
    REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. GO to FA7  .
  7. FA7 INTERMITTENT CHECK 
    • Ignition OFF.
    • For Fiesta,
    • IPC connector connected.
    • For all others,
    • PCM connector connected.
    • For Focus,
    • Right Exterior Rear View Mirror Assembly connector connected.
    • For all others,
    • AAT Sensor connector connected.
    • Ignition ON, engine OFF.
    • For Fiesta,
    • Access the PCM and monitor the OUTDR_TMP (TEMP) PID.
    • For all others,
    • Access the PCM and monitor the AAT (TEMP) PID.
    • While observing the PID, carry out the following:
      • Lightly tap on the sensor and wiggle the accessible harness from the sensor to the module.
      • Wiggle the connectors.
      • Look for sudden changes in the temperature when the sensor is tapped and the harness and connector are wiggled.

    Is a concern present? 

    Yes No
    REPAIR as necessary.
    Clear the PCM DTCs. REPEAT the self-test.    		 For Fiesta, GO to FA8  .
    For all others, GO to  FA9.
  8. FA8 TEMPERATURE SENSOR CORRELATION 
    NOTE: Check temperature values while engine is at ambient temperature, cold soak the engine for a minimum of 8 hours while not in direct sunlight, if necessary.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the ECT (TEMP), IAT (TEMP) and OUTDR_TMP (TEMP) PIDs.

    Are the temperature readings within 18°C (32.4°F) of each other? 

    Yes No
    GO to  FA10. INSTALL a new AAT sensor. REFER to the appropriate Climate Control article.
    RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .
    Clear the PCM DTCs. REPEAT the self-test.
  9. FA9 TEMPERATURE SENSOR CORRELATION 
    NOTE: Check temperature values while engine is at ambient temperature, cold soak the engine for a minimum of 8 hours while not in direct sunlight, if necessary.
    • Ignition ON, engine OFF.
    • Access the PCM and monitor the AAT (TEMP), ECT (TEMP) and IAT (TEMP) PIDs.

    Are the temperature readings within 18°C (32.4°F) of each other? 

    Yes No
    GO to  FA11. For Focus, INSTALL a new Right Exterior Rear View Mirror. REFER to the appropriate Rear View Mirrors article.
    For all others, INSTALL a new AAT sensor. REFER to the appropriate Climate Control article.
    RESET the keep alive memory (KAM). REFER to RESETTING THE KEEP ALIVE MEMORY (KAM) .
    Clear the PCM DTCs. REPEAT the self-test.
  10. FA10 CHECK FOR CORRECT INSTRUMENT PANEL CLUSTER (IPC) OPERATION 
    • Disconnect all the IPC connectors.
    • Visually inspect for:
      • pushed out pins
      • corrosion
    • Connect all the IPC connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.

    Is the concern still present? 

    Yes No
    INSTALL a new IPC. REFER to the appropriate Instrumentation article, Message Center, and Warning Chimes. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
  11. FA11 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.
    • 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) , Programming the VID Block for a Replacement PCM. The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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