P0711

Diagnostic Chart:

Wiring Diagram:

Circuit Description

The 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. The TFT range is -40 to +150°C (-40 to +302°F).

The PCM provides a 5 volt reference through a fixed series resistor to the TFT circuit, and monitors the voltage after the resistor, as the voltage drop (signal) across the circuit.

If the PCM detects a large, rapid, fluid temperature change, or essentially no change from a cold start-up, then DTC P0711 sets. DTC P0711 is a type D DTC.

Conditions for Setting the DTC

^ No Vehicle Speed Sensor (VSS) DTCs P0502 or P0503.

^ System voltage is 10-16 volts.

^ No Transmission Component Slipping DTC P1870.

^ The TFT at start up is -40 to 21°C (-40 to 69°F)

^ The engine run time is 5 minutes or more.

^ The vehicle speed is 8 km/h (5 mph) or more for 7 minutes or more, cumulative this ignition cycle.

^ The Torque Converter Clutch (TCC) slip speed is 120 RPM or more for 7 minutes, cumulative this ignition cycle.

^ The Engine Coolant Temperature (ECT) is 70°C (158°F) or more.

^ The ECT has changed 50°C (90°F) or more since start up.

^ The TFT voltage is 0.20-4.92 volts. All of the above must be true and one of the following fail cases must be true:

^ Fail Case 1

The change in TFT is 1.5°C (2.7°F) or less since start up for 7 minutes or more.

^ Fail Case 2

The change in TFT is 20°C (36°F) or more within 0.2 seconds for 14 times or more within 7 seconds.

Action Taken When the DTC Sets

^ The PCM does not illuminate the Malfunction Indicator Lamp (MIL).

^ The PCM calculates a transmission fluid default temperature as follows:

^ It any engine coolant temperature sensor codes are set, the PCM substitutes a transmission fluid temperature default value of 131°C (268°F).

^ If the engine coolant temperature is greater than 115°C (239°F), the PCM substitutes a transmission fluid temperature default value of 131°C (268°F).

^ If the engine run time is less than 3 minutes, the PCM substitutes the intake air temperature for the transmission fluid temperature value at start-up except if any inlet air temperature codes are set, the PCM sets default temperature to 0°C (32°F).

^ If engine run time is greater than 3 minutes and the engine coolant temperature is 45-115°C (113-239°F), the transmission fluid default temperature equals ECT-10°C when the intake air temperature is less than 0°C (32°F) at start-up. If the intake air temperature is greater than 28°C (82°F) at start-up, the transmission fluid default temperature equals ECT+10°C. If the intake air temperature (IAT) is 0 - 28°C (32-82°F) or any IAT DTC codes are set then transmission fluid default temperature is set to coolant temperature.

^ If the engine run time is greater than 3 minutes and the engine coolant temperature is less than 45°C (113°F), the transmission fluid default temperature is set to 12°C (54°F).

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 at the PCM, the transmission connector and all other circuit connecting points for the following conditions:

- A bent terminal.

- A backed out terminal.

- A damaged terminal.

- Poor terminal tension.

- A chafed wire.

- A broken wire inside the insulation.

- Moisture intrusion.

- Corrosion.

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

^ Refer to Specifications / Electrical / Temperature vs Resistance.

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

Test Description

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

2. This step tests for proper A/T fluid level and condition.

3. This step verifies which condition has set DTC P0711.

5. The 12-volt test lamp is used as a fixed resistance.

6. This step ensures that the PCM monitors circuit 1227.