P0218

DTC P0218

DTC Descriptor
This diagnostic procedure supports the following DTC:

DTC P0218 Transmission Fluid Overtemperature

Diagnostic Fault Information

Important:
Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview

Circuit/System Description
Transmission fluid is drawn from the bottom pan through the filter, case assembly, channel plate assembly, control valve body assembly and into the oil pump assembly. The pump is mounted on the control valve body assembly. Fluid pressure leaving the pump is controlled by the pressure regulator valve and becomes the main supply of line pressure to the various components and hydraulic circuits. Hot fluid from the torque converter flows through the torque converter clutch (TCC) control valve into the cooler lines to the oil cooler located in the vehicle radiator and auxiliary cooler, if equipped. Cool fluid then returns to lubricate the final drive assembly and other components along the output shaft.

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 130°C (266°F) for 10 minutes.

Action Taken When the DTC Sets
^ DTC P0218 is a type C DTC.
^ The transmission control module (TCM) freezes transmission adaptive functions.

Conditions for Clearing the DTC
DTC P0218 is a type C DTC.

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

Reference Information


DTC Type Reference
^ Diagnostic Trouble Code (DTC) Type Definitions
^ Diagnostic Trouble Code (DTC) List/Type

Circuit/System Verification
Ensure that the transmission fluid level is at the proper level by performing the Transmission Fluid Checking Procedure. Service and Repair

Circuit/System Testing
1. Perform the Transmission Fluid Checking Procedure. Service and Repair 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 Procedure. Line Pressure Check Procedure If the line pressure is low, refer to High or Low Line Pressure. 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 Oil Filter and Seal Replacement.
^ Plugged, kinked or damaged transmission cooler pipes-refer to Automatic Transmission Oil Cooler Flushing and Flow Test (J 45096) Component Tests and General Diagnostics Automatic Transmission Oil Cooler Flushing and Flow Test (J 35944-A). Component Tests and General Diagnostics
^ 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

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

Component Testing
^ Transmission Fluid Checking Procedure
^ Line Pressure Check Procedure
^ High or Low Line Pressure

Repair Instructions

Important:
Always perform the Diagnostic Repair Verification after completing the repair. Verification Tests

Ensure that the transmission fluid temperature is 129°C (264°F) or less for 5 seconds.