LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2000 >> Contour SE, 2.5 L, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 526 (Automatic Transmission) >> Diagnosis And Testing >> Pinpoint Tests - Non OSC Equipped Vehicles >> Pinpoint Tests >> Pinpoint Test B: Transmission Fluid Temperature (TFT) Sensor

Pinpoint Test B: Transmission Fluid Temperature (TFT) Sensor

WARNING: This page is about a different car, the 2004 Mercury Monterey and 2004 Ford Freestar. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Refer to TRANSAXLE VEHICLE HARNESS CONNECTOR  for the transaxle vehicle harness connector illustration.
NOTE: Refer to TRANSAXLE INTERNAL HARNESS DIAGRAM  for the transaxle internal harness diagram illustration.
  1. B1 ELECTRONIC DIAGNOSTICS 
    • Check to make sure the transaxle harness connector is fully seated, terminals are fully engaged in connector and in good condition before proceeding.
    • Have the above items been checked? 

    Yes 

    GO to B2.

    No 

    CARRY OUT checks. ERASE the codes. REPEAT the Quick Test.

  2. B2 CHECK THE ELECTRICAL SIGNAL OPERATION 
    CAUTION: Do not pry on the connector. This will damage the connector and could result in a transaxle concern. Pull up on the connector harness.
    • Key in OFF position.
    • Disconnect: Transaxle Vehicle Harness Connector.
    • Use a mirror to inspect both ends of the connector for damage or pushed out pins, corrosion, loose wires and missing or damaged seals.
    • Connect a VOM positive lead to the transmission fluid temperature (TFT) circuit pin 5 and the negative test lead to the signal return (SIG RTN) pin 9 of the transaxle vehicle harness connector.
    Fig 1: Checking Electrical Signal Operation
    G03244420Courtesy of FORD MOTOR CO.
    • Place VOM on the 20 volt scale.
    • Key in ON position.
    • Is the voltage between 4.75 and 5.25 volts? 

      Yes 

      GO to  B7.

      No 

      GO to B3.

  3. B3 CHECK THE CONTINUITY OF THE TFT AND SIG RTN CIRCUITS 
    • Key in OFF position.
    • Disconnect: Transaxle Vehicle Harness Connector.
    • Disconnect: Powertrain Control Module (PCM).
    • Inspect for damaged or pushed out pins, corrosion or loose wires.
    • Install the EEC-V Control System Breakout Box.
    • Measure the resistance between the powertrain control module (PCM) signal test pin 37 at the EEC-V Control System Breakout Box and the signal test pin 5 at the transaxle vehicle harness connector.
      Fig 2: Checking Continuity Of TFT And SIG RTN Circuits (1 Of 2)
      G03244421Courtesy of FORD MOTOR CO.
    • Measure the resistance between the PCM signal test pin 91 at the EEC-V Control System Breakout Box and the signal test pin 9 at the transaxle vehicle harness connector.
      Fig 3: Checking Continuity Of TFT And SIG RTN Circuits (2 Of 2)
      G03244422Courtesy of FORD MOTOR CO.
    • Is each resistance less than 5 ohms? 

      Yes 

      GO to B4.

      No 

      REPAIR the open circuits. REMOVE the EEC-V Control System Breakout Box. RECONNECT all of the components. REPEAT the Quick Tests.

  4. B4 CHECK THE TFT CIRCUIT FOR SHORT TO VPWR AND GROUND 
    • Inspect for damaged or pushed out pins, corrosion or loose wires.
    • Measure the resistance between the TFT test pin 37 and test pin 71 at the EEC-V Control System Breakout Box.
      Fig 4: Checking TFT Circuit For Short VPWR And Ground (1 Of 2)
      G03244423Courtesy of FORD MOTOR CO.
    • Measure the resistance between the TFT test pin 37 and chassis ground, pins 24, 25, 51, 76, 77, 91, and 103.
      Fig 5: Checking TFT Circuit For Short VPWR And Ground (2 Of 2)
      G03244424Courtesy of FORD MOTOR CO.
    • Is each resistance greater than 10,000 ohms? 

      Yes 

      GO to B5.

      No 

      REPAIR the short circuit(s). REMOVE the EEC-V Control System Breakout Box. RECONNECT all of the components. REPEAT the Quick Tests.

  5. B5 CHECK THE RESISTANCE OF THE TFT SENSORS/HARNESS 
    CAUTION: Do not pry on the connector. This will damage the connector and could result in a transaxle concern. Pull up on the connector harness.
    • Vehicle must be at normal operating temperature.
    • Disconnect: Transaxle Vehicle Harness Connector.
    • Connect the diagnostic tool.
    • Set the Bench/Drive switch to BENCH mode.
    • Rotate the Gear Select switch to OHMS CHECK position.
      NOTE: While carrying out test 1 and 2, observe resistance. DTC P0713 is set if resistance value exceeds 869K ohms (open circuit). DTC P0712 is set if resistance value falls below 597 ohms (short circuit).
    • Connect the ohmmeter negative lead to TFT jack and the positive lead to +TFT jack on tester.
      Fig 6: Checking Resistance Of TFT Sensors/Harness
      G03244425Courtesy of FORD MOTOR CO.
    • TEST 1 
    • Record the resistance.
    • Resistance should be approximately in the following ranges:
      TRANSMISSION FLUID TEMPERATURE/RESISTANCE SPECIFICATIONS

      °C °F Resistance (Ohms)
      -40 to -20 -40 to -4 967K-284K
      -19 to -1 -3 to 31 284K-100K
      0-20 32-68 100K-37K
      21-40 69-104 37K-16K
      41-70 105-158 16K-5K
      71-90 159-194 5K-2.7K
      91-110 195-230 2.7K-1.5K
      111-130 231-266 1.5K-0.8K
      131-150 267-302 0.8K-0.54K
    • TEST 2 
    • Check for intermittent short or open.
    • If the resistance was between 0.8K and 100K ohms carry out the following test. If the transaxle is warm, allow it to cool. Check the transmission fluid temperature sensor resistance again. Compare the resistance with the initial resistance. The resistance should decrease if the transaxle was heated and should increase if the transaxle was allowed to cool. If correct, then change in the resistance occurs, Repeat On-Board Diagnostic.
    • Is the resistance in the range? 

      Yes 

      GO to B6.

      No 

      GO to  B7.

  6. B6 CHECK THE SENSOR/HARNESS FOR SHORT TO GROUND 
    • Check for continuity between the BAT(-) jack (engine ground) and the appropriate jack (-TFT or +TFT) with an ohmmeter or other low current tester (less than 200 milliamps).
      Fig 7: Checking Sensor/Harness For Short To Ground
      G03244426Courtesy of FORD MOTOR CO.
    • Connection should show infinite resistance (no continuity).
    • Does the connection show continuity? 

      Yes 

      GO to B7.

      No 

      INSTALL a new PCM. REPEAT the On-Board Diagnostics; if the DTC is still present GO to B7.

  7. B7 INTERNAL ELECTRONIC DIAGNOSTICS 
    • Remove the transaxle side pan.
    • Check that the internal harness connector is fully engaged on the TFT sensor.
    • Check that the internal harness connector terminals are fully seated in the connector.
    • Inspect the connector for damage.
    • Are the above in good condition? 

      Yes 

      GO to B8.

      No 

      REPAIR as required.

  8. B8 CHECK THE INTERNAL HARNESS (CONTINUITY) 
    • Disconnect: Internal Harness From TFT Sensor.
      • CAUTION: Do not probe into the connector terminals. This will damage the connector and could result in a transaxle concern.
      Fig 8: Checking Internal Harness (Continuity) (1 Of 2)
      G03244427Courtesy of FORD MOTOR CO.
    • For the TFT sensor, connect the positive lead from an ohmmeter to the tester +TFT jack and the negative lead at the black wire of the TFT sensor connector.
    • Record the resistance. The resistance should be less than 0.5 ohms.
    • Connect the positive lead from an ohmmeter to the tester TFT jack and the negative lead at the white wire of the TFT sensor connector.
      Fig 9: Checking Internal Harness (Continuity) (2 Of 2)
      G03244428Courtesy of FORD MOTOR CO.
    • Record the resistance. The resistance should be less than 0.5 ohms.
    • Is the resistance less than 0.5 ohms? 

      Yes 

      GO to B9.

      No 

      INSTALL a new internal harness. GO to  B10.

  9. B9 CHECK THE INTERNAL HARNESS (SHORT TO GROUND) 
    • Check for continuity between BAT(-) jack (engine ground) and the appropriate wire (+TFT and -TFT) with an ohmmeter or other low current tester (less than 200 milliamps).
    Sensor Wire
    TFT+ Black
    TFT- White
    Fig 10: Checking Internal Harness (Short To Ground)
    G03244429Courtesy of FORD MOTOR CO.
    • Connection should show infinite resistance (no continuity).
    • Does the connection show continuity? 

      Yes 

      INSTALL a new internal harness. GO to B10.

      No 

      GO to B10.

  10. B10 CHECK THE TFT SENSOR RESISTANCE 
    • Check the sensor resistance by connecting an ohmmeter at the terminals of the TFT sensor assembly.
      Fig 11: Checking TFT Sensor Resistance
      G03244430Courtesy of FORD MOTOR CO.
    • Record the resistance.
    • The resistance should be in range of the temperature of the vehicle.
    • The resistance should be approximately in the following ranges:
      TRANSMISSION FLUID TEMPERATURE/RESISTANCE SPECIFICATIONS

      °C °F Resistance (Ohms)
      -40 to -20 -40 to -4 967K-284K
      -19 to -1 -3 to 31 284K-100K
      0-20 32-68 100K-37K
      21-40 69-10 437K-16K
      41-70 105-158 16K-5K
      71-90 159-194 5K-2.7K
      91-110 195-230 2.7K-1.5K
      111-130 231-266 1.5K-0.8K
      131-150 267-302 0.8K-0.54K
    • Is the resistance in the range? 

      Yes 

      GO to B11.

      No 

      INSTALL a new TFT sensor.

  11. B11 CHECK THE TFT SENSOR FOR SHORT TO GROUND 
    • Check for continuity between BAT(-) jack (engine ground) and the appropriate terminal with an ohmmeter or other low current tester (less than 200 milliamps).
    Sensor Wire
    TFT +/-
    Fig 12: Checking TFT Sensor For Short To Ground
    G03244431Courtesy of FORD MOTOR CO.
    • Connection should show infinite resistance (no continuity).
    • Does the connection show continuity? 

      Yes 

      INSTALL a new TFT sensor.

      No 

      REPEAT the Quick Test. If codes are present and an overtemperature condition existed, CHECK the fluid level and condition. Refer to PRELIMINARY INSPECTION . CHECK the overheat condition. Refer to DIAGNOSIS BY SYMPTOM . REPAIR as required. REPEAT the Quick Test.

scientia non olet · About LEMON Manuals