The Automatic Transmission Fluid Temperature (TFT) sensor is a negative coefficient thermistor. When the transmission fluid is cold, the sensor resistance is high. As the transmission fluid warms up, the sensor resistance becomes lower. The Powertrain Control Module (PCM) uses TFT information to control Torque Converter Clutch (TCC) apply and release, line pressure, and shift timing. The TFT range is -40°C to +151°C (-40°F to +304°F).

When the PCM detects a high transmission fluid temperature for an extended period of time on the TFT sensor circuit, then DTC P0218 sets. DTC P0218 is a type D DTC.

1. No TFT DTCs P0711, P0712, or P0713 are set.
2. The transmission fluid temperature is greater than 130°C (266°F) for 10 minutes.

1. A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.
2. The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the VCM.

The numbers below refer to the step numbers on the diagnostic table:

2. This step ensures that the transmission fluid is at the proper level. A low fluid level may cause an overtemperature condition.

3. This step inspects or repairs the following conditions:

•	Engine: Refer to Cooling and Radiator, Section 6.

•	Vehicle: Has the vehicle towed excessive weight?

•	Fluid: Refer to Transmission Fluid Check , Section 7.

•	Filter: Replace the filter if the filter is cracked or unseated.

•	Refer to Fluid Filter and Seal, in On-Vehicle Service.

•	Low Line Pressure: Inspect the cooler lines for any crimps or restrictions.

•	Refer to Line Pressure Check , Section 7.

•	Radiator: Refer to Cooling and Radiator, Section 6.