99 FLD120. Wiper switch problem

This started couple months ago. Driving and needed wipers on. Turned switch on. Wiper motor didn't come on. Turned switch on off a few times. While idling on off ramp. Wiper motor didn't come on.
I checked all the fuses in the panel, none were bad.

I hot wired the switch to get home.

I replaced the ignition switch. That didn't fix it. Then I replaced the wiper switch that didn't fix the problem.

Sometimes when I start the truck the wipers work.
Now before I start the truck I turn the wiper switch on, then I turn the key on. If the wipers move I start the truck. If they don't move, I'll turn the key off and on until the wipers move, then I'll start the truck.

Sometimes I have to key on/off several times before I start the truck.

The wipers will continue working using the switch until I turn the truck off.

My concern is the wiper motor not coming on at some point.
What electrical thingamajig is between the ignition switch and the wiper control switch?

I guess it's a bad relay, I can't read any labels on the relays. Can someone show me which relay is for the wipers.
Thanks.

 

The power problem is the feed to the wiper switch.
When the power is coming out of wiper switch the motor works.

 

Thanks for the replies.
The wiper motor coming on, Only works with the wiper dash switch having power out.

The power from the ignition switch into the dash switch is the problem.

When I hotwire direct from fuse panel to dash switch input the wiper motor works every time.

Is there a in line fuse or a relay in the circuit somewhere?

I suppose the dash switch I replaced could be bad same as the first. I'll try a third switch.
It doesn't act like a wiring problem because I can get the wiper to activate just sitting and toggle the switches.

 

No sensor.

 

If I turn ignition switch on and the wiper motor doesn't come on with the dash switch. I have turned dash switch on and off 30 times without the wiper motor coming on. BUT if I turn the ignition switch off and on again (it has taken up to 6 times) to get power to the dash switch to power the wiper motor.

As long as I don't turn the ignition switch off, the wiper switch operates normal. Couple days between starts.

I can try a different wiper motor. I don't think the motor is the problem.

 

That is the problem. Power to the dash switch.