P0218

DTC P0218

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



DTC Descriptor
DTC P0218
- Transmission Fluid Overtemperature




Circuit/System Description

The primary source of heat in the transmission is the torque converter. Hot oil exits the torque converter through the torque converter clutch (TCC) control valve and flows to the transmission cooler supply line. The supply line connects to the cooler, which is located in the radiator. From the cooler, the oil returns through the oil cooler return line and enters the lubrication circuits. After lubricating the internal components, the oil then returns to the oil pan. The oil pump draws oil through the filter from the oil pan, where the transmission fluid temperature (TFT) sensor is located. The oil pump pressurizes the oil and directs it to the pressure regulator valve. The pressure regulator valve is the starting point for the main supply of oil to the torque converter and the transmission hydraulic components.


Conditions for Running the DTC

The transmission fluid temperature is between -39 and +149°C (-38 and +300°F) for 5 seconds.


Conditions for Setting the DTC

The transmission fluid temperature is greater than 132°C (266°F) for 10 minutes.


Action Taken When the DTC Sets

* DTC P0218 is a Type C DTC.
* TRANSMISSION HOT - IDLE ENGINE displays on the driver information center (DIC).
* The transmission control module (TCM) freezes transmission adaptive functions.



Conditions for Clearing the DTC

DTC P0218 is a Type C DTC.


Diagnostic Aids

The DIC, if equipped, will display TRANSMISSION HOT - IDLE ENGINE when the transmission fluid temperature reaches 132°C (270°F).


Ask the customer about possible overloading, exceeding the trailer towing limit, or towing in overdrive.


Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Transmission General Description (Transmission General Description)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
Scan Tool Reference

Transmission Control Module Scan Tool Information (Scan Tool Testing and Procedures)


Circuit/System Verification

Ensure that the transmission fluid level is at the proper level by performing the Transmission Fluid Check (Transmission Fluid Check) .


Circuit/System Testing

1. Perform the Transmission Fluid Check (Transmission Fluid Check) .

• If the level is not within specifications, repair as necessary.

2. Inspect for the following conditions:

* Transmission line pressure low-refer to Line Pressure Check (Line Pressure Check) . If the line pressure is low, refer to High or Low Line Pressure.
* Transmission fluid flow through cooler and/or auxiliary cooler, if equipped, is restricted due to:

- Transmission fluid level low
- A clogged filter
- A leaking filter or seal-refer to Automatic Transmission Fluid Filter and Seal Replacement.

* A seized stator in the Torque Converter, refer to Torque Converter Diagnosis (Torque Converter Diagnosis) .
* Air flow through transmission fluid cooler and/or auxiliary cooler, if equipped, is restricted due to:

- Damaged fins
- Debris

* Engine overheating due to:

- Low coolant level-check coolant temperature, coolant level, and hoses
- Restricted air flow
- Restricted coolant flow-refer to Engine Overheating (Engine Overheating)




If any of the conditions listed are found, repair as necessary



Component Testing

* Transmission Fluid Check (Transmission Fluid Check)
* Line Pressure Check (Line Pressure Check)
* High or Low Line Pressure



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.