2000 Pontiac Montana Wipers Intermittent Mode They Park Instead Down Somehow

I have a 2000 Montana that had same issue....wipers staying in up position. Under hood there is a long black plastic cover that hides all of the arms and linkage that controls the wiper arms. I found all the linkage to be dry, so I lubricated the crap out of every single moving part under that cover with WD-40 or any lubricating fluid and it has worked perfect ever since. I now lube all the linkage every few months with no troubles again.