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 P502 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 wiring from the AT inline 20-way connector to the PCM for an open or short to voltage.
-
This step verifies the signal circuit from the PCM to the AT inline 20-way connector.
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 - 4.0L | ||||
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 - 4.0L | ||||
Refer to Automatic Transmission Inline 20-Way Connector End View . Is the voltage within the specified range? | 4.9-5.1 V | Go to Step 8 | Go to Step 4 | |||||
Is the voltage greater than the specified value? | 5.1 V | Go to Step 5 | Go to Step 6 | |||||
5 | 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 8 | Go to Step 13 | ||||
6 | Test the signal circuit (CKT 1227) of the TFT sensor for an open between the PCM connector C2 and the AT inline 20-way connector. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 7 | ||||
7 | Test the low reference circuit (CKT 2762) of the TFT sensor for an open between the PCM connector C2 and the AT inline 20-way connector. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 14 | Go to Step 13 | ||||
8 |
Refer to Automatic Transmission Inline 20-Way Connector End View . Is the resistance within the specified range? | 1,915-4,018 ohms @ 20-30°C (68-86°F) | Go to Intermittent Conditions in Engine Controls - 4.0L | Go to Step 9 | ||||
9 | Using the DMM and the J 35616-A , test for continuity between terminal L and all other terminals, except M, of the J 44152 . Refer to Automatic Transmission Inline 20-Way Connector End View . Did you find continuity between terminal L and another terminal other than M? | -- | Go to Step 11 | Go to Step 10 | ||||
10 |
Refer to Testing for Continuity in Wiring Systems. Did you find a condition? | -- | Go to Step 11 | Go to Step 12 | ||||
11 |
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 14 | -- | ||||
12 | 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 14 | -- | ||||
13 | Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.0L. Did you complete the replacement? | -- | Go to Step 14 | -- | ||||
14 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | Go to Step 15 | Go to Step 2 | ||||
15 | 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 - 4.0L | System OK |
