I have had this issue for a bit now, 98 GMC Jimmy.
To preface this I have replaced the wiper motor with a new pulse board, blower motor is newish same with the resistor.
First time this happened I parked the truck to diagnose at a later time, went to start the diag and wipers started working again, okay fine. Drive the truck for about 6 months wipers gave out, replaced the motor. Wipers work again, now I lost wiper function I also lost the blower motor. Checked fuses, all good even replaced a few for good measure. Wipers are still inoperable, and the blower still is not functioning. Test lead shows power getting to the plugs for both the wiper motor and the blower, I can't find my multimeter to check voltage at this time.
This seems to be an intermittent problem and I am trying to find the cause.
Any ideas? Any information is appreciated.

Thanks in advance