Power side mirror not working?

The first thing to do, is check the fuse #25 in the diagram. Also, use a voltage tester on the fuse circuit, goes hot when you turn on the key. Here is a guided to help you test the fuse and fuse power.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Here are the mirror wiring diagrams so you can see how the system works and the fuse locations as well. Check out the diagrams (Below). Please let us know what you find. We are interested to see what it is.

You should be on fuse 25, a ten-amp, on the left side of the dash. That fuse also feeds the heated seats and the heater control panel. If those work, you're either checking at the wrong fuse or your meter probe isn't making good contact with the fuse's test points.

The fuse gets 12 volts from the ignition switch, but there's a real lot of other circuits on that same line. To have a problem this far back, you'd have to have a lot of other dead stuff. Double-check that you're on the right fuse.

Don't make this more complicated than it needs to be. Do all those other circuits work? If they do, everything up to fuse 25 has to be good.

To clarify, you're checking for voltage, not current. Do you have one meter probe on a paint-free point on the body, and the other probe testing on the two test points on fuse 25? Some people get confused and put one probe on each fuse test point. You WILL read 0 volts that way, but that is not the way to test the circuit.

Check all fuses both in the vehicle and under the hood. Also, if they are all good, check body grounds and you may need to have the body control module tested.