P0218

Diagnostic Chart:

CIRCUIT DESCRIPTION

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 time. The TFT range is -40°C to +151°C (-40°F to +305°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 C DTC.


CONDITIONS FOR SETTING THE DTC

^ No ECT DTCs P0116, P0117 or P0118.

^ No TFT DTCs P0711, P0712 or P0713.

^ The engine coolant is greater than 0°C (32°F).

Failure Criteria:

Case 1

The transmission fluid temperature is greater than 130°C (266°F) for 30 minutes.

Case 2

The transmission fluid temperature is greater than 144°C (291°F) for 32 seconds.

ACTION TAKEN WHEN THE DTC SETS

^ The PCM does not illuminate the Malfunction Indicator Lamp (MIL).

^ IDLE ENGINE TRANSMISSION HOT message displays on the Driver Information Center.

^ DTC P0218 is stored in the PCM history.


CONDITIONS FOR CLEARING THE MIL/DTC

^ The PCM turns OFF the DIC after three consecutive trips without a failure reported.

^ The transmission fluid temperature must be less than 129°C (264°F) for more than 5 seconds.

^ 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.

^ 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 PCM.


DIAGNOSTIC AIDS

^ Inspect the transmission cooling system for possible blockage and restrictions.

^ Ensure that the transmission fluid is at the proper level

TEST DESCRIPTION

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 for the following conditions:

^ Engine: Refer to the Cooling System. Cooling System

^ Vehicle: Was the vehicle used to tow excessive weight?

^ Fluid: Refer to Transmission Fluid Checking Procedure.

^ Filter: Replace the filter if the filter is cracked or not seated. Refer to Filter Replacement, in On-Vehicle Service.

^ Scavenger Screens: Refer to Unit Repair.

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

Refer to The Pressure Check Procedure.

^ Radiator: Refer to the Cooling System. Cooling System