GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2008 🢒 Grand Prix 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC P0712 or P0713

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 provide an overview of each diagnostic category.

DTC Descriptors

DTC P0712:  Transmission Fluid Temperature (TFT) Sensor Circuit Low Voltage

DTC P0713:  Transmission Fluid Temperature (TFT) Sensor Circuit High Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

TFT Sensor Signal

P0712

P0713

P0713

P0218, P0711

Low Reference

--

P0713

--

P0218, P0711

Typical Scan Tool Data

Trans. Fluid Temp.

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Operating Conditions: Engine running in PARK, normal operating temperature

Parameter Normal Range: -40 to +149°C (-40 to +300°F)

Trans. Fluid Temp.

Greater than 149°C (300°F)

Less than -40°C (-40°F)

Less than -40°C (-40°F)

Circuit/System Description

The automatic TFT sensor is a thermistor. The TFT sensor is part of the automatic transmission fluid pressure (TFP) manual valve position switch. The transmission control module (TCM) supplies a 5-volt reference signal to the sensor. When the transmission fluid is cold, the sensor resistance is high and the TCM senses a high signal voltage. As the transmission fluid warms, the sensor resistance lowers and the TCM senses lower voltage. The TCM uses the TFT reading in order to control the torque converter clutch (TCC), line pressure adjustments, and temperature compensated shifts.

Conditions for Running the DTC
    • The ignition voltage is between 8.0 volts and 18 volts.
    • Engine speed is greater than 500 RPM for 10 seconds (0.6 minute) or greater.

Conditions for Setting the DTC

P0712

TFT is 150°C (302°F) or greater for 10 seconds.

P0713

TFT is -40°C (-40°F) or less for 400 seconds (7 minutes).

Action Taken When the DTC Sets
    • DTC P0712 and P0713 are type C DTCs.
    • The TCM freezes transmission adaptive functions.
    • The TCM calculates a default TFT based on engine coolant temperature (ECT), intake manifold air temperature, and engine run time.

Conditions for Clearing the DTC

DTC P0712 and P0713 are type C DTCs.

Diagnostic Aids
    • DTC P0712 detects a continuous short go ground in the TFT sensor signal circuit of the TFT sensor.
    • DTC P0713 detects a continuous open or short to voltage in the TFT sensor signal circuit of the TFT sensor.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation Reference

    •  Transmission General Information
    •  Transmission General Description
    •  Transmission Component and System Description
    •  Electronic Component Description
    •  Transmission Adaptive Functions
    •  Automatic Transmission Inline 20-Way Connector Description
    •  Powertrain Control Module 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

Control Module References for scan tool information

Special Tools

    • J 35616-64B Test Probe
    • J 35616-65B Test Probe
    • J 44152 Jumper Harness (20 pins)
    • J 44257 Main Wiring Harness Connector Remover

Circuit/System Verification
    • Start the engine. With the vehicle in PARK and at normal operating temperature, observe the Trans. Fluid Temp. parameter on the scan tool. The Trans. Fluid Temp. should display near the ECT sensor parameter.
    • 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 from the Freeze Frame/Failure Records data.

Circuit/System Testing

    Important: You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

  1. Ignition OFF, using the J 44257 main wiring harness connector remover, disconnect the automatic transmission inline 20-way connector and install the J 44152 jumper harness on the engine side of the automatic transmission 20-way connector.

    2. Important: 

       •  When probing a terminal for testing procedures, it is imperative to use the proper test probe from the J 35616-D GM terminal test kit. Prior versions of the J 35616 GM terminal test kit do not contain the proper probes for testing TCM/ECM/PCM connectors. TCM/PCM/ECM harnesses use 0.64 mm (0.03 in) round terminals. The correct probe for this size terminal is the light blue J 35616-64B probe. ALL PREVIOUS J 35616-64 AND J 35616-64A PROBES SHOULD BE DISCARDED. The 1.00 mm (0.04 in) brown J 35616-6 probe is most widely mistaken for use with 0.64 mm (0.03 in) terminals. Use of the 1.00 mm (0.04 in) brown probe in a 0.64 mm (0.03 in) terminal will deform the terminal, likely resulting in an intermittent open condition.
       • If a short to voltage is found, test the TFT sensor for damage.

  2. Ignition ON, using the light blue J 35616-64B probes, test for 4.9-5.1 volts between the TFT sensor signal circuit, jumper harness pin L, and a good ground.
    3. ⇒If the voltage is less than the specified range, test the TFT sensor signal circuit for an open, high resistance or short to ground.
    ⇒If the voltage is greater than the specified range, test the TFT sensor signal circuit for a short to voltage.
  3. Using the light blue J 35616-64B probes, test for 4.9-5.1 volts between the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M.
    4. ⇒If the voltage is less than the specified value, test the low reference circuit for an open, high resistance.
  4. Remove the J 44152 jumper harness from the engine side of the automatic transmission inline 20-way connector and install it on the transmission pass-thru connector.
  5. Using the light blue J 35616-65B test probes from the J 35616-D GM terminal test kit, test for 3,164-3,867 ohms of resistance at 20°C (68°F) between the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M. Refer to Transmission Fluid Temperature Sensor Specifications for the resistance at other temperatures.
    6. ⇒If greater than the specified range, test the affected circuits for an open/high resistance. If both circuits test normal, replace the TFT sensor.
    ⇒If less than the specified range, test the affected circuits for a shorted together condition. If both circuits test normal, replace the TFT sensor.
  6. Test for greater than 10K ohms of resistance between the TFT sensor signal circuit, jumper harness pin L, and all other circuits of the J 44152 jumper harness, except the TFT low reference circuit, jumper harness pin M.
    7. ⇒If less than the specified range, the affected circuits are shorted together. Replace the transmission internal wire harness.
  7. Test for greater than 10M ohms of resistance from the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M, to the transmission case.
    8. ⇒If less than the specified value, the affected circuit is shorted to the transmission case. Replace the transmission internal wire harness.
  8. If all circuits and connections test normal, replace the PCM .

Component Testing
  1. Remove the J 44152 jumper harness from the engine side of the automatic transmission inline 20-way connector and install it on the transmission pass-thru connector.
  2. Using the light blue J 35616-65B test probes from the J 35616-D GM terminal test kit, test for 3,164-3,867 ohms of resistance at 20°C (68°F) between the TFT sensor signal circuit, jumper harness pin L, and the TFT low reference circuit, jumper harness pin M. Refer to Transmission Fluid Temperature Sensor Specifications for the resistance at other temperatures.
    3. ⇒If greater than the specified range, test the affected circuits for an open/high resistance. If both circuits test normal, test the engine side of the TFT sensor signal circuit for a short to voltage AND replace the TFT sensor.
    ⇒If less than the specified range, test the affected circuits for a shorted together condition. If both circuits test normal, replace the TFT sensor.
  3. Test the PCM for supplying a 5-volt reference to the TFT sensor signal circuit, jumper harness pin L.
    4. ⇒If the PCM is not supplying a 5-volt reference to the TFT sensor, replace the PCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for TCM replacement, setup, and programming

Wiring Harness Replacement

Fluid Temperature Sensor Replacement