P0713

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 on circuit 1227. A low fluid temperature, an open TFT sensor or open circuits 1227 or 452 results in high signal voltage. The TFT operating range is -40 to +151°C (-40 to +304°F).
If the PCM detects a continuous open or a short to power on the TFT sensor circuit, then DTC P0713 sets. DTC P0713 is a Type D DTC.

Conditions for Running the DTC
The system voltage is 9-18 volts.

Conditions for Setting the DTC
The PCM detects a TFT sensor voltage greater than 4.92 volts for 6 minutes and 40 seconds continuous.

Action Taken When the DTC Sets
^ The PCM does not turn on the malfunction indicator lamp (MIL).
^ The PCM freezes shift adapts.
^ The PCM calculates a default TFT from the ECT sensor and the IAT sensor.
^ The PCM stores DTC P0713 in PCM history.

Conditions for Clearing the DTC
^ A scan tool clears the DTC from PCM history.
^ The PCM clears the DTC from PCM history if the vehicle completes 40 consecutive 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 ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids
^ Inspect the wiring at the PCM, the transmission 20-way connector and all Other circuit connecting points for the following conditions:
- A backed out terminal
- A damaged terminal
- Reduced terminal tension
- A chafed wire
- A broken wire inside the insulation
- Moisture intrusion
- Corrosion
^ When diagnosing for an intermittent open, massage the wiring harness while watching the test equipment for a change.
^ Test the TFT sensor at various temperature levels to evaluate the possibility of a skewed (mis-scaled) sensor.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. If the display does not indicate a TFT sensor voltage greater than 4.92 volts, inspect the connector and the terminals for intermittent conditions.

Important: After 10 seconds, the scan tool will display a default temperature.

4. This step tests the integrity of the engine harness and the PCM by using a fused jumper wire from terminal L to terminal M. Voltage should be less than 0.2 volts.
10. Because of the harsh conditions inside the transmission, repairing the automatic transmission (A/T) wiring harness assembly is not acceptable. It must be replaced if it is damaged in any way.