How do you check the transmission fluid in 2004 BMW 645 Ci?

To check the Transmission Fluid in a 2004 BMW 645Ci, first ensure the vehicle is on a level surface and the engine is running at normal operating temperature. Locate the transmission dipstick, which is typically found near the back of the engine; remove it, wipe it clean, and reinsert it fully before pulling it out again to check the fluid level. The fluid should be within the marked range on the dipstick and should have a reddish color and a clean smell. If the level is low, add the appropriate BMW transmission fluid through the dipstick tube.