P0218

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 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 are set.

^ No TFT DTCs P0711, P07l2 or PO713 are set.

^ 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 15 minutes.

^ Case 2: The transmission fluid temperature is greater than 144°C (291°F) for 32 seconds.


Action Taken When the DTC Sets

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

Conditions for Clearing the MIL/DTC

The transmission fluid temperature must be less than 120°C (248°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.


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:

1. This Step ensures that the Powertrain On-Board Diagnostic System Check was performed.

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: Was the vehicle used to tow excessive weight?

^ Fluid: Refer to Fluid Level Inspection.

^ 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 Line Pressure Check Procedure.

^ Radiator: Refer to Cooling and Radiator, section 6.