The automatic TFT sensor is a negative coefficient thermistor. The TFT sensor is part of the automatic transmission fluid pressure (TFP) manual valve position switch. The transmission control module (TCM) supplies a 5-volt reference signal to the sensor. When the transmission fluid is cold, the sensor resistance is high and the TCM senses a high signal voltage. As the transmission fluid warms up, the sensor resistance decreases and the TCM senses lower voltage. The TCM uses the TFT reading in order to control the torque converter clutch (TCC), line pressure adjustments, and temperature compensated shifts. This diagnostic monitors the TFT sensor circuit. The circuit may be functional but not in the normal operating range. This diagnostic indicates stuck, erratic, intermittent, or skewed values, resulting in reduced system performance. The TFT sensor range is -40 to +150°C (-40 to +304°F).

Condition 1

The TFT has changed by less than 1.5°C (2.7°F) 409 seconds (7 minutes) after start-up.

Condition 2

The TFT has changed by greater than 20°C (36°F), 14 times within 7 seconds (0.12 minute).

DTC P0711 is a type C DTC.

DTC P0711 detects a TFT that remains constant for a period of time, in which a measurable amount of change is expected, or a TFT in which large rapid unrealistic changes occur in a very short period of time.

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

1. Ignition OFF, using the J 44257 main wiring harness connector remover, disconnect the automatic transmission inline 20-way connector and install the J 44152 jumper harness on the engine side of the automatic transmission 20-way connector.
2. Turn ON the ignition, with the engine OFF. Observe the Trans. Fluid Temp. parameter on the scan tool. If the Trans. Fluid Temp. is -40°C (-40°F), replace the TFT sensor.

Important: 

•

When probing a terminal for testing procedures, it is imperative to use the proper test probe from the J 35616-D GM terminal test kit. Prior versions of the J 35616 GM terminal test kit do not contain the proper probes for testing TCM/ECM/PCM connectors. TCM/ECM/PCM harnesses use 0.64 mm (0.03 in) round terminals. The correct probe for this size terminal is the light blue J 35616-64B probe. ALL PREVIOUS J 35616-64 AND J 35616-64A PROBES SHOULD BE DISCARDED. The 1.00 mm (0.04 in) brown J 35616-6 probe is most widely mistaken for use with 0.64 mm (0.03 in) terminals. Use of the 1.00 mm (0.04 in) brown probe in a 0.64 mm (0.03 in) terminal will deform the terminal, likely resulting in an intermittent open condition.

•	If a short to voltage is found, test the TFT sensor for damage.

3. Ignition ON, using the light blue J 35616-64B probes, test for 4.9-5.1 volts between the TFT sensor signal circuit, jumper harness pin L, and a good ground.

⇒	If the voltage is less than the specified range, test the TFT sensor signal circuit for an open, high resistance, or short to ground.

⇒	If the voltage is greater than the specified range, test the TFT sensor signal circuit for a short to voltage.

4. Using the light blue J 35616-64B probes, test for 4.9-5.1 volts between the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M.

⇒	If the voltage is less than the specified value, test the low reference circuit for an open, high resistance.

5. Remove the J 44152 jumper harness from the engine side of the automatic transmission inline 20-way connector and install it on the transmission pass-thru connector.
6. Using the light blue J 35616-65B test probes from the J 35616-D GM terminal test kit, test for 3,164-3,867 ohms at 20°C (68°F) between the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M. Refer to Transmission Fluid Temperature Sensor Specifications for the resistance at other temperatures.

⇒	If greater than the specified range, test the affected circuits for an open/high resistance. If both circuits test normal, replace the TFT sensor.

⇒	If less than the specified range, test the affected circuits for a shorted together condition. If both circuits test normal, replace the TFT sensor.

7. Test for greater than 10K ohms between the TFT sensor signal circuit, jumper harness pin L, and all other circuits of the J 44152 jumper harness, except the TFT low reference circuit, jumper harness pin M.

⇒	If less than the specified range, the affected circuits are shorted together. Replace the transmission internal wire harness.

8. Test for greater than 10M ohms from the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M, to the transmission case.

⇒	If less than the specified value, the affected circuit is shorted to the transmission case. Replace the transmission internal wire harness.

9. If all circuits and connections test normal, replace the PCM.

1. Using the light blue J 35616-65B test probes from the J 35616-D GM terminal test kit, test for 3,164-3,867 ohms at 20°C (68°F) between the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M. Refer to Transmission Fluid Temperature Sensor Specifications for the resistance at other temperatures.

⇒	If greater than the specified range, test the affected circuits for an open/high resistance. If both circuits test normal, test the engine side of the TFT sensor signal circuit for a short to voltage AND replace the TFT sensor.

⇒	If less than the specified range, test the affected circuits for a shorted together condition. If both circuits test normal, replace the TFT sensor.

2. Test the PCM for supplying a 5-volt reference to the TFT sensor signal circuit, jumper harness pin L.

⇒	If the PCM is not supplying a 5-volt reference to the TFT sensor, replace the PCM.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.