Diagnostic Instructions
DTC Descriptor
DTC P0218: Transmission Fluid Overtemperature
Diagnostic Fault Information
Component
| Condition
| DTCs
|
Engine
|
| • | Engine coolant level low |
| • | Incorrect engine coolant |
| • | Old coolant or incorrect concentration level |
| • | Radiator hose kinked or pinched |
| • | Loose, missing, or damaged radiator air seals or deflector - poor air flow |
| • | The radiator and A/C condenser has air flow obstructions to include large amount of bent fins |
| • | The cooling fans do not operate |
| • | Inspect the engine mechanical for worn, leaking, cracked cylinder heads, or engine block |
| P0218
|
Transmission
| Vehicle Overload or Beyond Capacity Towing:
| • | Vehicle is towing beyond capacity |
| P0218
|
Heat Transfer:
| • | Cooler restrictions - radiator has restricted flow/blockage |
| • | Aftermarket auxiliary cooler installed incorrectly, incorrect flow direction - reversed flow |
| • | Restricted, blocked, or pinched transmission cooler lines. |
| P0218
|
Transmission Abuse:
| • | Vehicle is towing beyond capacity |
| P0218
|
Transmission Fluid:
| • | Contaminated or poor fluid quality |
| P0218
|
Torque Converter:
| • | Torque converter inoperative or affected - stator, pump, clutch, ballooning or heat damaged |
| P0218
|
Low Pump Output:
| • | Blocked, damaged or loose filter |
| • | Pinched or restricted cooler lines |
| • | Restricted cooler - damage or debris |
| • | Inefficient pump - worn |
| P0218
|
Clutch Slippage:
| P0218
|
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 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 returns to the oil pan. The transmission fluid temperature (TFT) sensor is located
in the control solenoid valve assembly.
Conditions for Running the DTC
| • | The ignition voltage is between 10.2 V -15.5 V. |
| • | The engine speed is greater than 400 RPM for 2 s. |
| • | The transmission is not in emergency mode. |
| • | Transmission control module (TCM) communication is normal. |
Conditions for Setting the DTC
| • | Vehicle speed less than 180 km/h (112 MPH) and transmission fluid temperature more than 150°C (302°F) for more than 10 s. |
| • | Vehicle speed more than 180 km/h (112 MPH) and transmission fluid temperature more than 150°C (302°F) for more than 60 s. |
Action Taken When the DTC Sets
| • | DTC P0218 is a Type C DTC |
| • | Warning message to the driver via CAN bus. |
Conditions for Clearing the DTC
| • | DTC P0218 is a Type C DTC. |
| • | Vehicle speed less than 170 km/h (106 MPH) and transmission fluid temperature less than 140°C (284°F) for more than 3 s. |
| • | Vehicle speed more than 170 km/h (106 MPH) and transmission fluid temperature less than 140°C (284°F) for more than 3 s. |
Diagnostic Aids
Ask the customer whether their typical day-to-day driving include:
| • | Trailer towing should occur in D4. |
| • | Hauling or vehicle overloading. |
| • | Extreme off-road conditions. |
| • | Ensure the engine cooling system is functioning normally. |
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Component Connector End Views
Electrical Information Reference
Description and Operation
Transmission Indicators and Messages
Transmission Component and System Description
Transmission Overheats
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Verify the transmission fluid level , colour and odor is correct.
- Review the Freeze Frame when the DTC set.
| ⇒ | If the engine coolant temperature (ECT) was above 125°C (257°F) when the DTC set, go to
Engine Overheating and correct that concern first. |
Circuit/System Testing
Dynamic Test
- Inspect the transmission cooling system for restrictions or damage, inducing any auxiliary cooler if equipped.
- Perform the Transmission Fluid Cooler Flushing and Flow Test to verify proper transmission oil cooler flow.
| ⇒ | If a concern is found, repair or replace the damaged components as necessary. |
- Perform the Line Pressure Check to verify proper transmission line pressure.
| ⇒ | If a concern is found repair or replace the damaged components as necessary. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
