P0712

Diagnostic Chart 1 Of 2:

Diagnostic Chart 2 Of 2:

Schematic:

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 high fluid temperature or a short to ground on circuit 1227 results in low signal voltage. The TFT sensor operating range is -40 to +151°C (-40 to +304°F).

If the PCM detects a continuous short to ground in TFT sensor circuit 1227, then DTC P0712 sets. DTC P0712 is a type C 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 less than 0.2 volts for 10 seconds.

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 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 P0712 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 connectors at the controller, the component and all other circuit connecting points for an intermittent condition. Refer to Testing for Intermittent and Poor Connections in Diagrams.
^ Inspect the circuit wiring for an intermittent condition. Refer to Testing for Electrical Intermittents in Diagrams.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests the PCM's ability to detect an open circuit.
5. This step tests the TFT sensor for correct resistance.