P0218

Circuit Description

The 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, the sensor resistance decreases. The TFT range is -40 to +150°C (-40 to +302°F).

When the PCM detects a low TFT sensor resistance (high transmission temperature) for an extended period of time, then DTC P0218 sets. DTC P0218 is a type D DTC.

Conditions for Running the DTC

No TFT DTCs P0711, P0712 or P0713.

Conditions for Setting the DTC

DTC P0218 sets when the transmission fluid temperature is greater than 130°C (286°F) for more than 10 minutes.

Action Taken When the DTC Sets

The PCM does not illuminate the malfunction indicator lamp (MIL).

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.

Diagnostic Aids

^ Inspect the wiring at the PCM, the transmission 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
^ Check for a faulty TFT sensor by reading resistance at various temperature levels, and comparing to the Temperature vs Resistance table.
^ When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change.
^ Inspect the transmission cooling system for blockage and restrictions.

Test Description

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

3. This step determines if an electrical condition exists.
5. This step checks the TFT sensor against the Temperature vs Resistance table.