I did a motor swap in my 1998 gmc k2500 and when I was done the wipers came on

What is your question?

Automatically when the switch was in the off position. I changed out the wiper motor control board but had no luck . The bed is off of the truck and the rear tail light harness is not hooked up. Could the tail light harness not being hooked up cause the windshield wipers to automatically turn on (high speed)when I start the truck? Im currently doing body work to the bed and thats why it is off of the truck. Just hoping for a quick fix.