It could also be the switch. They are easy to clean. Just remove the screws holding the panel on the door and gently pry back the panel. Leave it attached at the top (pain in the <img src="/forums/images/graemlins/butwiggle.gif" alt="" /> to put it back on). I prop them away at the bottom with a screw driver so I can access the switch. Unplug it first, then remove. The switch has 2 spring clips that hold it in place. Simply depress one side and it should release with ease. The switch may have some small screws holding it together (front doors). I think the rear door switches just have plastic retaining tabs (don't break them). The switch has some small metal rockers that work the contacts. They can fall out - be careful when you open the switch so you don't lose them. My contacts were covered with carbon-like crud. It brushes off easily. Clean both the contacts and the rockers, then pop it all back together and reassemble. The first one might be a bit of a trick. But the rest will be easy.

As Dryver noted, you can also test the motor at the same time. You can do that using the power from the connector to the switch (and confirm you have power to the switch - key must be "on"). You will have to ground the ground wire to the body with a jumper. Then you can use another jumper from the hot-lead to test the motor's up and down movement. Hope that helps...

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