P0711

DIAGNOSTIC TROUBLE CODE (DTC) P0711 TRANSMISSION FLUID TEMPERATURE (TFT) SENSOR CIRCUIT RANGE/PERFORMANCE





Circuit Description
The Automatic Transmission Fluid Temperature (TFT) sensor assembly is a thermistor and is part of the Automatic Transmission Fluid Pressure Manual Valve Position Switch Assembly (TFP Val. Position Sw.). The Powertrain Control Module (PCM) supplies a 5-volt reference signal to the sensor on circuit 506. When transmission fluid is cold, the sensor resistance is high and the PCM senses a high signal voltage. As the transmission fluid warms, the sensor resistance lowers and the PCM senses lower voltage. The PCM uses the TFT readings to control Torque Converter Clutch (TCC) line pressure adjustments, and temperature compensated shifts.
When the PCM detects one of the following unusual conditions, then Diagnostic Trouble Code (DTC) P0711 sets.
1. An unrealistically large change in transmission temperature.
2. A value which remains constant for a period of time in which a measurable amount of change is expected.

Conditions For Setting The DTC
- Engine is running.
- System voltage is between 9 - 16 volts.
- No Vehicle Speed Sensor (VSS) codes P0722 or P0723.
- No Input Shaft Speed (ISS) codes P0716 or P0717.
- Vehicle speed is greater than 8 km/h (5 mph) for 409 seconds, cumulative.
- Transmission startup temperature is between -40° and 21°C (-40° and 69.8°F).
- TCC slip speed is greater than 120 rpm for more than 900 seconds, cumulative.
- Engine Coolant Temperature is greater than 70°C (158°F).
- Engine Coolant Temperature has changed by more than 50° since start up.
- All of the above must be true and one of the following fail cases must be true:

Fail Case 1
- Transmission temperature has not changed more than 1.5°C (2°F) since start-up.

Fail Case 2
- Transmission temperature changes more than 20°C (36°F) within 200 milliseconds.

Action Taken When The DTC Sets
- The PCM will illuminate the Malfunction Indicator Lamp (MIL) after two consecutive ignition cycles with a failure reported.
- DTC P0711 is stored in the PCM history.
- The PCM freezes shift adapts from being updated.
- The PCM calculates transmission temperature based on engine coolant temperature, intake manifold air temperature and engine run time.

Conditions For Clearing The DTC

Fail Case 1
- The TFT changes by more than 2.25 degrees for at least 5 seconds.

Fail Case 2
- The TFT does not change by more than 20 degrees within 0.200 second for a period of at least 11 seconds.
- History DTCs can be cleared by using a Scan Tool.

Diagnostic Aids
- Inspect the wiring for poor electrical connections at the PCM and at the transmission 20-way connector. Look for possible bent, backed out, deformed or damaged terminals. Check for weak terminal tension as well. Also check for chafed wire that could short to bare metal or other wiring. Inspect for broken wire inside the insulation.
- If diagnosing for a possible intermittent short or open condition, move or massage the wiring harness while observing test equipment for a change.

Test Description
The numbers below refer to the step numbers on the diagnostic chart.
6. This step checks for an intermittent short or open condition in the engine wiring harness. The test light is used as a resistor in the circuit.
7. This step determines if the PCM or the TFT sensor is causing a steady, unchanging TFT reading.








DTC P0711 - Transmission Fluid Temperature (TFT) Sensor Circuit Range/Performance