Circuit Description
The automatic transmission fluid temperature (TFT) sensor is a negative coefficient thermistor whose resistance value changes based on temperature. The PCM provides a 5 volt reference to the sensor. A low fluid temperature or open circuit result in high signal voltage. The TFT operating range is -40 to +151°C (-40 to +305°F).
If the PCM detects a continuous open or a short to voltage on the TFT sensor circuit, then DTC P0713 sets. DTC P0713 is a type C DTC.
Conditions for Running the DTC
| • | No VSS DTCs P0502 or P0503. |
| • | No AT ISS DTCs P0716 or P0717. |
| • | The engine run time is greater than 5 seconds. |
| • | The transmission output shaft speed is 200 RPM or greater for 5 minutes cumulatively. |
| • | The TCC slip speed is 50 RPM or greater for 6 minutes and 40 seconds cumulatively. |
Conditions for Setting the DTC
The PCM detects a reading of -40°C (-40°F) or less for 6 seconds.
Action Taken When the DTC Sets
| • | The PCM does not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM calculates a default transmission fluid temperature based on engine coolant temperature, intake air temperature and engine run time. |
| • | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records. |
| • | The PCM stores DTC P0713 in PCM history. |
Conditions for Clearing the DTC
| • | A scan tool can clear the DTC. |
| • | The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring. |
| • | The PCM cancels the DTC default actions when the fault no longer exists and the DTC passes. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests the TFT sensor signal circuit for being shorted to another circuit within the transmission. If the TFT sensor signal circuit shorts to another circuit, which is carrying voltage greater than five volts, the TFT sensor would become open.
-
This step tests the TFT sensor signal circuit for being shorted to voltage, which would be the cause for the open in the TFT sensor.
Step | Action | Value(s) | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | Go to Diagnostic System Check - Engine Controls in Engine Controls | ||||
2 |
Important: Before clearing the DTC, use the scan tool in order to record the DTC Failure Records. Using the Clear Info function erases the Failure Records from the PCM. Does the scan tool display a Trans. Fluid Temp. less than the specified value? | -39°C (-38°F) | Go to Step 3 | Go to Intermittent Conditions in Engine Controls | ||||
3 |
Refer to Automatic Transmission Inline 20-Way Connector End View . Is the resistance less than the specified value? | 100 K ohms | Go to Step 7 | Go to Step 4 | ||||
4 |
Refer to Testing for Continuity in Wiring Systems. Did you find an open condition? | -- | Go to Step 8 | Go to Step 5 | ||||
Measure the resistance between terminal L and all other terminals of the J 44152 . Is the resistance between terminal L and any other terminal less than the specified value? | 1000 ohms | Go to Step 10 | Go to Step 6 | |||||
Test the signal circuit (CKT 1227) of the TFT sensor for a short to voltage between the PCM connector C2 and the AT inline 20-way connector. Refer to Testing for a Short to Voltage and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 9 | |||||
7 |
Refer to Testing for Continuity and Wiring Repairs in Wiring Systems. Did you find and correct an open condition? | -- | Go to Step 12 | Go to Step 11 | ||||
8 |
Important: The automatic transmission wiring harness consists of two separate harnesses, the Automatic Transmission Wiring Harness Assembly, GM P/N 15320475 and the Automatic Transmission Wiring Extension Harness Assembly, GM P/N 15320478. In order to avoid the unnecessary replacement of parts, only replace the Automatic Transmission Wiring Harness Assembly, GM P/N 15320475. Replace the automatic transmission wiring harness. Refer to Input Speed Sensor and Wiring Harness Removal in the 4T80-E section of the Transmission Unit Repair Manual. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
9 | Replace the TFT sensor. Refer to Control Valve Upper Body Disassemble in the 4T80-E section of the Transmission Unit Repair Manual. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
10 |
Important: The automatic transmission wiring harness consists of two separate harnesses, the Automatic Transmission Wiring Harness Assembly, GM P/N 15320475 and the Automatic Transmission Wiring Extension Harness Assembly, GM P/N 15320478. In order to avoid the unnecessary replacement of parts, only replace the Automatic Transmission Wiring Harness Assembly, GM P/N 15320475. Refer to Input Speed Sensor and Wiring Harness Removal in the 4T80-E section of the Transmission Unit Repair Manual. Did you complete the replacements? | -- | Go to Step 12 | -- | ||||
11 | Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
12 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 13 | Go to Step 2 | ||||
13 | With the scan tool, observe the stored information, capture info. and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List in Engine Controls | System OK |
