Wiper motor intermittently stopping

If you have ever had one apart you will find three small wires that hold the brushes to the armature. These are the thickness of a hair. Any moisture inside the cover causes these to rust and fail. I do not advise trying to take one apart and fixing it. Unless you have a lot of patience, tweasers and a steady hand. Check the ground 1st, should be a copper strap on one of the wiper post studs. Wiper motors rebuilt are relatively cheap rebuilt. I am a tight wad but this is one of those things that I just buy a rebuilt one. Keep the arm off the back of wiper motor as they do not come with it. It is held on with 1/2 nut