95 F-150 help! erratic windsheild wiper operation

I have a 1995 Ford F-150 pickup 2WD no power windows or doorlocks. My windsheild wipers turn on at any time they please without touching the switch at all. Somone told me its a common ford problem but they didnt know what the fix was. I read in another forum from sombody that they had the same problem and they replaced the combination switch and it fixed it but it was the only thing i have found so far that is relitive to this problem at all. I couldent find any TSB's or anything relitive to this problem. Any one else see this problem or have any suggestions?

There is a TSB for the multifunction switch for your problem. The switch should repair your problem.

There is also a FMC S bulletin for this, check and see if your wiper relay is bad.