Code P0218, Control MOD?

Hi,

That is a tough one to answer because there are different possibilities. If I had the vehicle in my shop, here is a list of things I would check and in the order, I would check it. Keep in mind, it could be something as simple as the low or contaminated fluid.

First, here is an overview of the system. These vehicles are equipped with a transmission fluid cooler/warmer assembly. The transmission fluid cooler/warmer maintains the transmission fluid at operating temperature. When the transmission fluid is below operating temperature the transmission fluid heater coolant control valve will direct heated engine coolant to the transmission fluid cooler/warmer to heat the transmission fluid to operating temperature in an optimal amount of time. When the transmission fluid rises above the operating temperature the transmission fluid cooler coolant control valve will direct cooled engine coolant to the transmission fluid cooler/warmer to reduce the transmission fluid temperature to normal operating temperature.

Here is where I would start.

Inspect the transmission fluid level and condition to ensure it meets the manufacturer's specifications. Also, if the fluid is extremely dirty, I would check the transmission cooler.

Check the wiring and connectors in the transmission fluid temperature sensor circuit for any signs of damage, corrosion, or loose connections.

Test the transmission fluid temperature sensor's resistance to determine if it is providing accurate readings.

Address any other underlying issues, such as cooling system problems, which could be contributing to the transmission overheating.

If you look below, I attached things to check from the manual which really parallel what I mentioned. The last three pics are to help you locate the different components.

Let me know exactly what is happening. Also, make sure to check the fluid level and condition, and check for leaks. Also, let me know if that is the only code present, if the transmission is in limp mode, slipping, or not working at all.

Let me know if this helps.

Take care,

Joe

See pics below.