Circuit Description
The automatic transmission fluid temperature (TFT) sensor is a thermistor. The TFT sensor is part of the automatic transmission fluid pressure (TFP) manual valve position switch. The PCM supplies a 5-volt reference signal to the sensor. When the transmission fluid is cold, the sensor resistance is high and the PCM senses a high signal voltage. As the transmission fluid warms, the sensor resistance lowers and the PCM senses lower voltage. The PCM uses the TFT reading in order to control the torque converter clutch (TCC), line pressure adjustments, and temperature compensated shifts.
When the PCM detects a continuous open or short to voltage in the TFT circuit or the TFT sensor, then DTC P0713 sets. DTC P0713 is a type C DTC.
Conditions for Running the DTC
| • | The ignition switch is in the ON position. |
| • | The system voltage is 8-18 volts. |
Conditions for Setting the DTC
The TFT voltage is 4.92 volts or greater for 6 minutes and 40 seconds.
Action Taken When the DTC Sets
| • | The PCM does not illuminate the malfunction indicator lamp (MIL). |
| • | The PCM freezes transmission adapt functions. |
| • | The PCM calculates a default transmission fluid temperature based on engine coolant temperature, intake manifold 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 Powertrain Diagnostic System Check? | -- | 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 TFT sensor voltage greater than the specified value? | 4.92 V | Go to Step 3 | Go to Intermittent Conditions in Engine Controls | ||||
3 |
Refer to Automatic Transmission Inline Harness 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 Circuit Testing 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? | 1,000 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 Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 9 | Go to Step 9 | |||||
7 |
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. 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 Transmission Overhaul in Transmission Unit Repair Manual. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
9 | Replace the TFP manual valve position switch. Refer to Pressure Switch Assembly Replacement. Did you complete the replacement? | -- | Go to Step 12 | -- | ||||
10 |
Refer to Transmission Overhaul in Transmission Unit Repair Manual. Refer to Pressure Switch Assembly Replacement. 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? | -- | System OK | Go to Step 1 |
