This could be a couple of issues so the way we need to figure this out is to start checking power through the wiper system when the wipers are on, and the switch is off.
Basically, we need to find out where the power is coming from. This is most likely a short or connection issue but normally a loose connection normally causes them to cut off.
On newer vehicles when the module loses connection it will default the wipers on as a safety measure. This vehicle does not have this.
So I suspect this issue is there is a wire that is rubbed through and when you hit the right bump it grounds out and turns the wipers on.
I am attaching the wiring diagram below but let's start at the motor and work backwards when the wipers are on to find where we do not have power.
Let me know if you have questions on this but this could be a relay issue as well so let's start with this and go from there.
Images (Click to enlarge)
Thursday, June 2nd, 2022 AT 8:27 AM