P0218

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION
The Automatic Transmission Fluid Temperature (TFT) Sensor is a thermistor that controls the signal voltage to the Vehicle Control Module (VCM). The VCM supplies a 5-volt reference to the sensor on circuit 1227. When the transmission fluid is cold, the sensor resistance is high and the VCM senses high signal voltage. As the fluid temperature warms to a normal transmission operating temperature, the TFT Sensor resistance becomes less and the voltage decreases.
If the VCM detects a high transmission fluid temperature (TFT) for a long period of time, then DTC P0218 sets. DTC P0218 is a type D DTC.

CONDITIONS FOR SETTING THE DTC
^ No TFT Sensor DTCs P0712 or P0713.
^ The TFT is greater than 135°C (277°F).
^ All conditions are met for 410 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The VCM freezes shift adapts from being updated.
^ The VCM does not illuminate the Malfunction Indicator Lamp (MIL).

CONDITIONS FOR CLEARING THE DTC
1. A scan tool can clear the DTC from the VCM history. The VCM clears the DTC from the VCM history if the vehicle completes 40 warm-up cycles without a failure reported.
2. The VCM 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.

DIAGNOSTIC AIDS
^ Inspect the cooling system fluid level and condition.
^ Inspect the transmission cooler and the transmission cooler lines for damage or restrictions.
^ The scan tool Trans. Fluid Temp. (TFT) should rise steadily then stabilize.
^ Inspect for a possible torque converter stator problem.
^ Verify the customer's driving habits, such as trailer towing, etc.
^ First diagnose and clear any engine DTCs or Throttle Position (TP) Sensor codes that are present. Then inspect for any transmission DTCs that may have reset.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests for a skewed sensor or shorted Circuit.
4. This step simulates a TFT DTC P0713.