on a ford escape which battery cable do you take off first to clear the check engine light

Always disconnect the Negative cable first.

Billy is correct always remove the neg 1st and when reinstalling cables install the possative 1st as well. its eliminates arc problems mostly. by the way l think you need to get them cleared with the scanner rather than the cables.

The negative cable is always the first off & the last one on.

If u choose to clear the check engine light by removing the battery cable, keep in mind that u will have to run the vehicle through a complete drive cycle (anywhere from 30-50 miles) for the computer to reset & be able to be tested again.

So, in other words, if you're doing this to pass inspection, it wo not work.
If you're doing it to clear codes after you've fixed a problem, u wo not know for 30-50 miles whether you've been successful or not.
Better to get a scanner & clear them that way.

Disconnecting your battery will not turn off the engine light, it will only return when you run the engine after twelve hours. You must manually clear the code that is present to turn off the engine light., with a code reader.

Either one,but preferably negative,so if touching something will not have a short.