P0218

P0218 - High Temperature Operation Activated

For a complete wiring diagram, refer to.

Theory of Operation

If the transmission oil temperature rises above 115 °C (240 °F), the overheat shift schedule is activated, and the code is set. The DTC is an informational code only and is being set to aid the technician in determining root cause of a customer driveability issue. The code is also intended to alert the technician to determine if a cooling system malfunction has occurred or if an additional transmission air to oil cooler should be added to the vehicle if the customer regularly drives in a manner that overheats the transmission. Extended operation above 115 °C (240 °F) will reduce the durability of the transmission and should be avoided. Correcting the cooling system malfunction or installing an additional transmission oil cooler will improve transmission durability especially for customers who operate in city/construction stop and go traffic, tow trailers regularly, drive aggressively in low gear or drive regularly in mountainous areas.

• When Monitored: Whenever the engine is running.

• Set Condition: Immediately when a overheat shift schedule is activated when the transmission oil temperature reaches 115 °C or 240 °F.






Always perform the pre-diagnostic troubleshooting procedure before proceeding. Refer to => Non-DTC Based Diagnostics. Pre-Diagnostic Troubleshooting Procedure

Test Step 1 - Check the Engine Cooling System

• Perform Engine Cooling System diagnostics. Refer to => Engine DTC Based Diagnostics.

Is the cooling system functioning properly?

Yes

• Go to Test Step 2.

No

• Repair the cause of the engine overheating.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

Test Step 2 - Transmission Oil Cooler Restricted

• Check the transmission oil cooler flow.

Is the transmission oil cooler restricted or plugged?

Yes

• Repair or replace the transmission oil cooler.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test

No

• Go to Test Step 3.

Test Step 3 - High Temperature Operation

• This DTC is an informational DTC designed to aid the technician in diagnosing shift quality complaints.

• This DTC indicates that the transmission has been operating in the "overheat" shift schedule which may generate a customer complaint.

• The customer driving patterns may indicate the need for an additional transmission oil cooler.

• With the scan tool, check the DTC event data to help identify the conditions in which the DTC was set.

• Check the service bulletins for any possible causes that may apply.

If there are no possible causes remaining, view repair.

Repair

• Repair the cause of transmission overheating.

• Perform the Transmission Verification Test. Refer to => Non-DTC Based Diagnostics. Transmission Verification Test