Diagnostic Instructions
DTC Descriptor
DTC P0218: Transmission Fluid Overtemperature
Circuit/System Description
The flow of transmission fluid starts in the bottom pan and is drawn through the filter, control valve body assembly, transmission case and into the oil pump assembly. The oil pump assembly pressurizes the fluid and directs it to the pressure regulator
valve where it becomes the main supply of fluid to the various components and hydraulic circuits in the transmission. Hot fluid exiting the torque converter flows through the converter clutch apply valve and into the transmission cooler lines to the oil cooler
located in the vehicle radiator, and auxiliary cooler if equipped. From the cooler, fluid returns to cool and lubricate the front of the transmission. In forward drive ranges, D4 fluid from the manual valve is routed through an orificed cup plug in the rear
of the transmission case to feed the rear lube fluid circuit.
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 136°C (277°F) or greater for 60 seconds.
Action Taken When the DTC Sets
• | DTC P0218 is a Type C DTC. |
• | TRANS 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 TRANS 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
Connector End View Reference
Component Connector End Views
Description and Operation
Transmission General Information
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Transmission Control Module Scan Tool Information
Circuit/System Verification
Ensure that the transmission fluid level is at the proper level by performing the
Transmission Fluid Check
.
Circuit/System Testing
Inspect for the following conditions:
• | Transmission fluid flow through cooler and/or auxiliary cooler, if equipped, is restricted due to: |
- | Transmission fluid level low |
• | Air flow through transmission fluid cooler and/or auxiliary cooler, if equipped, is restricted due to: |
• | Engine overheating due to: |
- | Low coolant level--Check coolant temperature, coolant level, and hoses. |
⇒ | If any of the conditions listed are found, repair as necessary. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the repair.