For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC P0711: Transmission Fluid Temperature (TFT) Sensor Performance

### Circuit/System 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 up, 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, skewed, or inaccurate values, indicating poor system performance. The TFT range is -40 to +151°C (-40 to +305°F). If the transmission control module (TCM) detects rapid or no voltage changes in the TFT sensor circuit, then DTC P0711 sets.

### Conditions for Running the DTC

• | No ECT DTC P0115.

• | No ISS DTCs P0716 or P0717.

• | No OSS DTCs P0722 or P0723.

• | DTC P0711 has not passed in the current ignition cycle.

• | The transmission fluid temperature is -39 to +149°C (-38 to +300°F).

#### Condition 1

• | The engine coolant temperature (ECT) is at least 70°C (158°F) and has changed by 50°C (122°F) since start up.

• | The vehicle speed is 8 km/h (5 mph) or more for at least 5 minutes cumulative.

• | The torque converter clutch (TCC) slip is 120 RPM or more for at least 15 minutes cumulative.

#### Condition 2

• | The engine coolant temperature is at least 70°C (158°F) and has changed by 50°C (122°F) since start up.

• | The vehicle speed is 8 km/h (5 mph) or more for at least 10 minutes cumulative.

#### Condition 3

• | The calc. throttle position is between 8 and 100 percent.

• | The engine torque is 50 N·m (37 lb ft) or more.

• | The vehicle speed is 8 km/h (5 mph) or more.

• | The engine speed is greater than 500 RPM.

### Conditions for Setting the DTC

One of the following conditions occurs:

#### Condition 1

• | The transmission fluid temperature at startup is -40 to +20°C (-40 to +68°F).

• | The vehicle speed is greater than 8 km/h (5 mph) for 300 seconds (5 minutes) cumulatively.

• | The transmission fluid temperature has not changed by more than 2°C (4°F) since startup for 100 seconds (1 minute and 40 seconds).

#### Condition 2

• | The transmission fluid temperature at startup is 129-150°C (264-302°F).

• | The vehicle speed is greater than 8 km/h (5 mph) for 300 seconds (5 minutes) cumulatively.

• | The transmission fluid temperature has not changed by more than 2°C (4°F) since startup for 100 seconds (1 minute and 40 seconds).

#### Condition 3

The transmission fluid temperature has changed by 20°C (36°F) or greater within 250 milliseconds; 14 times within 7 seconds.

### Action Taken When the DTC Sets

• | DTC P0711 is a Type C DTC.

• | The TCM freezes transmission adaptive functions.

• | The TCM calculates a default transmission fluid temperature based on engine coolant temperature, intake air temperature and engine run time.

### Conditions for Clearing the DTC

DTC P0711 is a Type C DTC.

### Diagnostic Aids

The DIC, if equipped, will display TRANSMISSION HOT - IDLE ENGINE when the transmission fluid temperature reaches 132°C (270°F).

Ask the customer about possible overloading, exceeding the trailer towing limit, or towing in overdrive.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Transmission General Description

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Transmission Control Module Scan Tool Information

#### Special Tools

J 45681 Jumper Harness

### Circuit/System Verification

Ensure that the transmission fluid level is at the proper level by performing the Transmission Fluid Check.

Drive the vehicle while observing the Trans. Fluid Temp. parameter on the scan tool. The Trans. Fluid Temp. parameter should rise by 3°C (5°F) or more.

### Circuit/System Testing

1. Start the engine and observe the Trans. Fluid Temp. parameter on the scan tool. Drive the vehicle while observing the Trans. Fluid Temp. parameter. The Trans. Fluid Temp. parameter should rise by 3°C (5°F).

⇒ | If the Trans. Fluid Temp. does not rise by 3°C (5°F), turn OFF the ignition.

2. Disconnect the AT 20-way inline connector. Turn ON the ignition with the engine OFF. Observe the Trans. Fluid Temp. parameter on the scan tool. The Trans. Fluid Temp. should display -40°C (-40°F).

⇒ | If the Trans. Fluid Temp. is -40°C (-40°F), replace the TFT sensor.

3. Using a DMM, measure the voltage on the TFT sensor signal circuit on the engine harness side of the AT 20-way inline connector and ground. The voltage should be near 5 volts.

⇒ | If the voltage is not near the specified value, repair the open or high resistance in the TFT sensor signal circuit.

⇒ | If an open or high resistance is not found, test the TCM.

4. Measure the voltage between the TFT sensor signal circuit and the low reference circuit at the AT 20-way inline connector. The voltage should be near 5 volts.

⇒ | If the voltage is not near the specified value, repair the open or high resistance in the low reference circuit.

5. Using the J 45681 jumper harness, measure the resistance between the TFT sensor signal circuit and the low reference circuit at the transmission side of the AT 20-way inline connector. Refer to Temperature Versus Resistance. The resistance should be between the specified range for the given temperature.

⇒ | If the resistance is not within the specified range for the given temperature, replace the TFT sensor.

### Component Testing

1. Disconnect the AT 20-way inline connector and measure the resistance between the TFT sensor signal circuit and the low reference circuit. Refer to Temperature Versus Resistance.

⇒ | If the resistance is not within the specified range for the given temperature, replace the TFT sensor.

2. Test the TCM for supplying the 5-volt reference circuit to the TFT sensor.

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

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

• | Manual Shift Shaft Position Switch Replacement

• | Refer to Control Module References for TCM replacement, setup, and programming.

• | Transmission Internal Electrical Harness Replacement