When it goes in one direction, you know the motor is okay. The polarity is reversed by the four sets of contacts in the switch. Barring a cable-driven mechanism that has the cable fraying and getting tangled, the cause of being dead in one direction is almost always due to pitted switch contacts. I haven't found one yet that I couldn't get apart to clean on a Chrysler product. A lot of GMs use a bizarre switch setup with a sealed relay. Those I've had to replace the switch. With yours, you might want to find a switch at a salvage yard to verify that is the cause, or, if you're adventurous, you can take it apart and see if you can get to the contacts to clean them.
Use a thin strip of sandpaper folded over and slide it into the contacts. There's going to be two contacts that you have to press on by hand to put pressure on the sandpaper, and there's going to be two that you have to open up to allow the sandpaper to slide in. Normally only one contact is bad. It will usually be visibly blackened or have a tiny black arced spot in the middle.
Two of those contacts are in the circuit for each direction.
Monday, January 27th, 2014 AT 10:18 AM