Circuit Description
The automatic transmission fluid temperature (TFT) sensor is part of the automatic transmission fluid pressure (TFP) manual valve position switch. The TFT sensor is a thermistor, or a resistor that changes value when the temperature changes. The sensor has a negative-temperature coefficient. This means that as the temperature increases, the resistance decreases, and as the temperature decreases, the resistance increases. The transmission control module (TCM) supplies a 5-volt reference signal to the sensor and measures the voltage drop in the circuit. When the transmission fluid is cold, the sensor resistance is high and the TCM detects high signal voltage. As the fluid temperature increases, the resistance of the sensor decreases, which lowers the signal voltage.
If the TCM detects an open or short to voltage in the TFT sensor or signal circuit, then DTC P0713 sets. DTC P0713 is a type C DTC.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Voltage
Conditions for Running the DTC
| • | No OSS DTCs P0722, P0723. |
| • | The output shaft speed is 200 RPM or greater for 200 or more seconds (3 minutes and 20 seconds) cumulative. |
| • | The TCC slip speed is 120 RPM or greater for 200 or more seconds (3 minutes and 20 seconds) cumulative. |
| • | The engine run time is greater than 5 seconds. |
Conditions for Setting the DTC
The TCM detects a transmission fluid temperature of -39°C (-38°F) or less for 400 seconds.
Action Taken When the DTC Sets
| • | The TCM does not request the ECM to illuminate the malfunction indicator lamp (MIL). |
| • | The TCM commands elevated line pressure. |
| • | 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. |
| • | The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record. |
| • | The TCM stores DTC P0713 in TCM history. |
Conditions for Clearing the DTC
| • | A scan tool can clear the DTC. |
| • | The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring. |
| • | The TCM 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 that is greater than 5 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 | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||
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 transmission control module (TCM). Does the scan tool display a Trans. Fluid Temp. less than the specified value? | -39°C (-38°F) | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections | ||||
3 |
Refer to Automatic Transmission Inline 20-Way Connector End View . Does the resistance measure less than the specified value? | 100 K ohms | Go to Step 7 | Go to Step 4 | ||||
4 |
Refer to Testing for Continuity . Did you find an open condition? | -- | Go to Step 8 | Go to Step 5 | ||||
Measure the resistance between the TFT sensor signal circuit and all other terminals of the J 44152 . Refer to Testing for Continuity . Does the resistance measure less than the specified value? | 1000 ohms | Go to Step 10 | Go to Step 6 | |||||
Test the signal circuit of the TFT sensor for a short to voltage between the TCM and the AT inline 20-way connector. Refer to Testing for a Short to Voltage and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 9 | |||||
7 |
Refer to Testing for Continuity and Wiring Repairs . Did you find and correct an open condition? | -- | Go to Step 12 | Go to Step 11 | ||||
8 | Replace the automatic transmission wiring harness. Refer to Valve Body and Pressure Switch Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
9 | Replace the TFT sensor. Refer to Valve Body and Pressure Switch Replacement . Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
10 |
Refer to Valve Body and Pressure Switch Replacement . Did you complete the replacements? | -- | Go to Step 12 | -- | ||||
11 | Replace the TCM. Refer to Control Module References for replacement, setup, and programming. 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? | -- | System OK |
