DTC P0712 - TFT Sensor Circuit Low Voltage / High Temp
Circuit Description
The transaxle fluid temperature (TFT) sensor is a thermistor that varies resistance according to changes in transaxle fluid temperature. The powertrain control module (PCM) supplies 5-volt reference through a pull-up resistor to the sensor, which is connected to ground. When the sensor is cold it has high resistance, high signal voltage at PCM. As the sensor temperature increases, its resistance decreases, lower signal voltage at PCM. The PCM uses the signal voltage to determine transaxle fluid temperature. DTC P0712 sets when the TFT sensor signal voltage at the PCM is below the calibrated voltage value, over the calibrated temperature value.
DTC Parameters
DTC P0712 will set if TFT sensor temperature is over 140°C (284°F), TFT sensor voltage less than 0.2 volts when:
| • | The condition exists for longer than 30 seconds |
| • | The condition exists twice in one ignition cycle |
| • | The ECT is less than 100°C (212°F) |
| • | No ECT or IAT DTCs have been set |
DTC P0712 diagnostic runs continuously once the above conditions have been met.
DTC P0712 is a type A DTC.
Diagnostic Aids
To locate an intermittent problem, use scan tool to monitor TRANS. FLUID TEMP with ignition ON, engine OFF. Wiggling wires while watching for a change in TRANS. FLUID TEMP may locate the area where a short to ground in the wiring could lie.
Transaxle fluid leaking from the sensor into the sensor connector will cause a shorted condition across the sensor terminals resulting in an elevated temperature.
Refer to DTC P0710 for a Temperature vs. Resistance chart.
