P0711

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The Automatic Transmission Fluid Temperature (TFT) sensor is a negative coefficient thermistor. When the transmission fluid is cold, the sensor resistance is high. As the transmission fluid warms, the sensor resistance decreases. This diagnostic monitors the TFT circuit. The circuit may be functional, but not in the normal operating range. This diagnostic indicates stuck, erratic, intermittent, or skewed values, indicating poor system performance. The TFT range is -40 to +151°C (-40 to +305°F).

When the PCM detects an intermittent voltage or no voltage change in the TFT sensor circuit, then DTC P0711 sets. DTC P0711 is a type B DTC.

Conditions for Setting the DTC

^ No Vehicle Speed (VSS) sensor DTCs P0502 or P0503 are set.

^ No A/T 155 DTCs P0716 or P0717 are set.

^ The transmission fluid temperature at start-up is -40 to 21°C (-40 to 70°F).

^ System voltage is 9-16 volts.

^ The engine run time is more than 5 minutes.

^ The vehicle speed is greater than 8 km/h (5 mph) for 6 minutes and 49 seconds.

^ The TCC slip is greater than 300 RPM for 6 minutes and 49 seconds.

^ The engine coolant temperature is more than 70°C (158°F).

^ The engine coolant temperature has changed by more than 50°C (90°F) since start-up.

Failure Criteria

Case 1: The change in transmission fluid temperature is less than 1.5°C (2°F) since start-up for 1 minute and 20 seconds.

Case 2: The change in transmission fluid temperature is greater than 20°C (36°F) within 200 milliseconds; 14 times within 7 seconds.

Action Taken When the DTC Sets

^ The PCM illuminates the Malfunction Indicator Lamp (MIL) after two consecutive trips with a failure reported.

^ The PCM freezes shift adapts from being updated.

^ The PCM calculates a default transmission fluid temperature based on engine coolant temperature, manifold air temperature, and engine run time.

^ DTC P0711 is stored in the PCM history.

Conditions for Clearing the DTC

^ A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.

^ The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the PCM.

Diagnostic Aids

^ Inspect the wiring for poor electrical connections at the PCM. Inspect the wiring for poor electrical connections at the transmission 20-way connector. Look for the following conditions:

- A bent terminal

- A backed out terminal

- A damaged terminal

- Poor terminal tension

- A chafed wire

^ Test the TFT sensor at various temperature levels to evaluate the possibility of a skewed (mis-scaled) sensor.

^ When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change.

^ Inspect the transmission 20-way connector for transmission fluid.

Test Description

The numbers below refer to the Step numbers on the diagnostic table.

5. This step tests for an intermittent short or open condition in the engine wiring harness. The test light is used as a resistor in the circuit.

6. This Step determines if the PCM or the TFT sensor is causing a steady, unchanging TFT reading.