Automatic Transmission Fluid Warming Valve

Regarding the operation of the ATF  warming valve the following 3 phases can be differentiated:

• Warm-up phase - Hot engine coolant from the thermostatic valve of the ATF  cooler is directed to the ATF  cooler. This provides a reduced ATF  warm-up time.
• Temperature control phase - Hot engine coolant from the thermostatic valve of the ATF  cooler and cold engine coolant coming from the radiator are mixed. This provides an accurate control to maintain the ATF  at the desired operation temperature
• Cooling phase - Cold engine coolant from the radiator is directed to the ATF  cooler to provide the maximum ATF  cooling capability.