Wipers being weird

ight guys this one has stuped the hell outta me..ok when the car is running off an accessory the wipers will work all day long...untill you turn the truck on..then they will work for a few seconds and turn off..i bought a new motor...same problem..so then i thought that the alternator was puting out too much voltage and maybe it was freakin the wipers out..so i started the truck and unplugged the alternator.. and they were running just fine..so i bought a new alternator and its still doing the same thing..when i turn the truck on they work but only for a few seconds...if anyone has any ideas help would be much appriciated..this is really starting to make me mad lol

I had that problem in my 89, they would come on at random, etc wouldnt shut off. I Took the turn signal lever out, cleaned the contacts, and they work like they should again. Try that worked for me