Allison - Automatic Transmission
DTC P0711
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptor
DTC P0711
- Transmission Fluid Temperature (TFT) Sensor Circuit Low Performance
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The transmission fluid temperature (TFT) sensor is a 2 wire sensor located in the pressure switch manifold (PSM). The transmission control module (TCM) supplies a signal circuit and a low reference circuit to the TFT sensor. The resistance of the TFT sensor decreases as the oil temperature increases. The TCM monitors the voltage drop across the TFT sensor and calculates the temperature of the transmission fluid in the oil pan.
Conditions for Running the DTC
All Conditions
* DTCs P0711, P0716, P0717, P0721, P0722, or P0742 is not set.
* Battery voltage is between 9-18 V.
* Engine speed is greater than 200 RPM for 5 seconds.
* The TFT was between -39°C (-38°F) and 149°C (300°F) at startup.
* The engine coolant temperature is not defaulted.
Additional Condition 1
* The TFT was between -40°C (-40°F) and 21°C (70°F) at startup.
* The engine coolant temperature (ECT) is 70°C (158°F) or greater and has increased by 15°C (27°F) since start up.
* The torque converter clutch (TCC) slip speed is 120 RPM or more for at least 5 minutes.
Additional Condition 2
* TFT was between 115°C (239°F) and 150°C (302°F) at startup.
* ECT is 70°C (158°F) or greater and has increased by 55°C (99°F) since start up.
* The TCC slip speed is 120 RPM or more for at least 5 minutes.
Additional Condition 3
* Engine torque is greater than 150 Nm (110 lb ft).
* Vehicle speed is greater than 22 km/h (14 mph).
* Throttle is 10.5 percent or greater.
* Engine speed is 500 RPM or greater.
* ECT is between -39°C (-38°F) and 149°C (300°F).
Additional Condition 4
Induction air temperature (IAT) is not defaulted.
Conditions for Setting the DTC
Condition 1
The TFT has not risen 2°C (4°F) since startup for 2 minutes and the vehicle speed is greater than 8 km/h (5 mph) for 5 minutes.
Condition 2
The TFT has not risen 3°C (5°F) since startup for 2 minutes and the vehicle speed is greater than 8 km/h (5 mph) for 5 minutes.
Condition 3
The TFT changes 20°C (36°F) or greater in consecutive readings 14 times in 7 seconds.
Condition 4
The TFT does not reach 20°C (68°F) within a period of time that varies with TFT at start up.
Condition 5
At startup when engine speed is greater than 500 RPM for 2 seconds and ECT is between -39°C (-38°F) and 50°C (122°F), if the difference between IAT and ECT is less than 6°C (11°F) and the difference between ECT and TFT is greater than 40°C (72°F), or if the difference between IAT an ECT is greater than 6°C (11°F) and the difference between ECT and TFT is greater than 60°C (108°F).
Action Taken When the DTC Sets
* DTC P0711 is a Type B DTC.
* The TCM uses a calibration default value for TFT.
Conditions for Clearing the DTC
DTC P0711 is a Type B DTC.
Diagnostic Aids
You may have to drive the vehicle in order to experience a condition.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics (Allison - Automatic Transmission)
Connector End View Reference
* Component Connector End Views (Connector End Views By Name)
* Inline Harness Connector End Views (Connector End Views By Number)
Description and Operation
* Transmission General Description (Transmission General Description)
* Transmission Component and System Description (Transmission Component and System Description)
* Electronic Component Description (Electronic Component Description)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Control Module References) for scan tool information
Circuit/System Verification
1. Perform the Transmission Fluid Level and Condition Check (Transmission Fluid Level and Condition Check) to verify correct fluid level and condition.
2. Perform the Road Test (Allison - Automatic Transmission) while observing the Trans. Fluid Temp. with a scan tool. The Trans. Fluid Temp. parameter should rise steadily to a normal operating temperature, and then stabilize.
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed on the Freeze Frame/Failure Records data.
Circuit/System Testing
Note: You must perform the Circuit/System Verification first.
1. Ignition OFF, disconnect the X175 harness connector at the transmission.
2. Ignition ON, engine OFF, connect a 3A fused jumper wire between the TFT signal circuit terminal pin G and the TFT low reference circuit terminal H. Verify with a scan tool that the Trans. Fluid Temp. parameter changes from -40°C (-40°F) to 160°C (320°F).
• If not the specified value, test the TFT signal circuit and low reference circuit for a short to voltage, short to ground or an open/high resistance. If circuits test normal, replace the TCM.
3. Ignition OFF, remove the transmission oil pan. Refer to Oil Pan Replacement (Allison - Automatic Transmission).
4. Test the transmission internal harness TFT signal and low reference circuits for a short to voltage, short to ground or an open/high resistance.
• If circuits test normal, test or replace the pressure switch manifold.
Component Testing
Static Testing
Note: You must perform the Circuit/System Testing first.
1. Ignition OFF, remove the pressure switch manifold from the valve body. Refer to Pressure Switch Manifold Replacement (Service and Repair).
2. Test for resistance between the signal circuit terminal E, and the low reference circuit terminal F. See transmission fluid temperature sensor table, refer to Temperature Versus Resistance (Transmission Fluid Temperature Sensor) (Temperature Versus Resistance (Transmission Fluid Temperature Sensor))Temperature Versus Resistance (Speed Sensor) (Temperature Versus Resistance (Speed Sensor))Temperature Versus Resistance (Solenoid) (Temperature Versus Resistance (Solenoid)).
• If not within the specified range, replace the pressure switch manifold, with thermistor.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Wiring Harness Replacement (Allison - Automatic Transmission)
* Pressure Switch Manifold Replacement (Service and Repair)
* Control Module References (Control Module References) for TCM replacement, setup, and programming
Repair Verification
If another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle (Diagnostic Trouble Code (DTC) List - Vehicle) and perform the appropriate diagnostic procedure.