B4000 Regular Cab 4WD V6-4.0L OHV (1997)
Transmission Fluid Temperature Sensor: Description and Operation
TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR
Detects transmission fluid temperature. Sensor resistance affects voltage drop across sensor terminals and provides electrical signals to PCM
corresponding to temperature. PCM controls the following:
1. Shift scheduling for cold fluid
2. Inhibits TCC operation
3. Electronic Pressure Control (EPC) Solenoid
NOTE: Uses thermistor devices. Resistance changes with temperature:
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Resistance decreases as temperature increases.
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Resistance increases as temperature decreases.
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Sensor is connected to voltage divider so that varying resistance of sensor causes a variation in total current flow. Dropped voltage across a fixed
resistor in a series with sensor determines voltage signal at PCM.
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If the transmission fluid temperature sensor circuit has an open or short, Diagnostic Trouble Code No. P0712, P0713, or P1711 is output.
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If the transmission fluid temperature sensor is open or shorted, erratic shifting may be felt.