Which would be removed on a vehicle transmission/transaxle without a dipstick to check the fluid level?

When dealing with a vehicle transmission or transaxle that lacks a dipstick for monitoring fluid levels, the most common method for checking the fluid level involves removing a specific plug, commonly referred to as the fill or level plug.

The fill plug is positioned on the transmission case and allows access for checking the fluid level. When you remove this plug, transmission fluid should be at the opening if it's at the correct level; if no fluid comes out, then it's likely time to add more. This method is particularly relevant for certain vehicles designed without dipsticks, as it provides a straightforward way to ensure the proper amount of fluid is present for optimal operation.

While the other options, such as removing a pan, a sensor, or a switch, could pertain to different maintenance procedures or repairs, they do not directly relate to the straightforward task of checking transmission fluid levels in vehicles lacking a dipstick. The pan is usually involved in servicing or changing the fluid, while the sensor and switch are more related to electrical diagnostics than fluid level checks. Thus, focusing on the removal of the fill plug is the appropriate action in this scenario.