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Home >> Ford >> 2000 >> Contour SE, 2.0 3, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 1807 (Automatic Transmission - 4R70E/4R75E - F150 & Mark LT) >> Diagnostic Tests >> Pinpoint Tests - OSC Equipped Vehicle >> 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 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Refer to the Transmission Internal Harness illustration Transmission Connector Layouts  in this article.
  1. B1 ELECTRONIC DIAGNOSTICS 
    • Check to make sure the transmission harness connector is fully seated, pins are fully engaged in connector and in good condition before proceeding.
    • Connect the diagnostic tool.
    • Key in ON position.
    • Select Diagnostic Data Link.
    • Select PCM.
    • Select PID/Data Monitor and Record.
    • Enter the following diagnostic mode on the diagnostic tool: PIDs; TFT, TFTV
    • Does the vehicle enter PID/Data Monitor and Record? 
    1. YES  : Go to  B2.
    2. NO  : REPEAT procedure to enter PID. If vehicle did not enter PID, REFER to the INTRODUCTION - GASOLINE ENGINES article for diagnosis of PCM.
  2. B2 WARM-UP/COOL-DOWN CYCLE 
    • While monitoring the transmission fluid temperature (TFT) PIDs, carry out the following test: If transmission is cold, run transmission to warm it up. If transmission is warm, allow transmission to cool down.
    • Do the TFT PIDs increase as the transmission is warmed up or decrease as the transmission is cooled, or does the TFT or TFTV drop in and out of range? 
    1. YES  : If the TFT PIDs increase as the transmission is warmed or decrease as the transmission is cooled, CLEAR all DTCs. ROAD TEST to verify if concern is still present. If concern is still present, REFER to Diagnosis By Symptom  in this article to diagnose transmission overheating.

      If the TFT or TFTV drop in and out of range, INSPECT for intermittent concern in the internal/external harness, sensor or connector.

    2. NO  : Go to  B3.
  3. B3 ELECTRICAL SIGNAL CHECK 
    • Key in ON position.
    • Remove transmission fluid pan.
    • Visually inspect the molded lead frame and connectors for damage.
    • Measure the voltage with the positive lead to positive TFT at sensor pin and negative lead to a good ground.
      • Fig 1: Checking Electrical Signal
      GF0003442Courtesy of FORD MOTOR CO.
    • Is the voltage present? 
    1. YES  : Go to  B4.
    2. NO  : CHECK for open or short circuit in vehicle harness, internal harness or a PCM concern.
  4. B4 CHECK RESISTANCE OF TFT SENSOR 
    • Disconnect: Transmission Harness
    • Measure the resistance between the positive TFT and negative TFT pins at transmission connector, using the following:
      TRANSMISSION FLUID TEMPERATURE

      °C °F Resistance (Ohms)
      -40 to -20 -40 to -4 967K - 284K
      -19 to -1 -3 - 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
      • Fig 2: Measuring Resistance Between Positive TFT And Negative TFT Pins At Transmission Connector
      GF0003443Courtesy of FORD MOTOR CO.
    • Is the resistance correct? 
    1. YES  : REFER to Diagnosis By Symptom  in this article to diagnose an overheating concern.
    2. NO  : INSTALL a new internal harness (sensor is part of harness).
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