DIAGNOSIS The float switch in the internal drain pan is stuck in the "up" position, tricking the unit into thinking there's water when there isn't. Dust, sludge, or a misaligned float can cause this. On these Midea models, the auto-evaporation usually handles condensation, so this light coming on falsely is a common glitch.
FIX Unplug the unit. Locate drain port on the back or bottom—it's a small rubber or plastic plug. Place a shallow pan under it and pull the plug to let any trace moisture out. Then, gently tilt the unit from side to side and back to front. You're trying to free up that little plastic float inside the pan. Plug the drain, set the unit level, plug it in, and see if the light turns off.
IF THAT DIDN'T WORK You might need to access the float. Unplug the unit and remove all the exterior screws from the rear lower panel (keep them organized). Carefully remove the panel to see the black plastic drain pan. Look for a small, white, box-like float switch. Manually move its arm up and down a few times to ensure it's free. Reassemble and test.
HEADS UP Never operate the unit with drain plug open. It will suck in unfiltered air and can damage the pump or coil. Always ensure it's sealed tight for normal operation.