04 s-10 factory fog lights

I have an 04 s-10 4X4 and I have installed the factory fog lights and the factory switch in the dash. It appears the the switch olny sends a short signal to the bcm which turns the fog light relay on. Dose anyone know how to program the bcm so that the fog lights work.

Is the relay there for the fog lights?

yes, the relay is there, The switch on the dash sends a ground to the bcm. The bcm grounds the relay to switch on the fog lights. I have tested all the wires and it stops at the bcm.

new relay needed?

Bad ground?

Wired Properly?

All the wires were pre wired in the truck from the facory, I did test all of them and all good. The relay was replaced with the horn relay and, same result, horn still works, so not relay problem. I connection stops at the bcm. Why would fog lights go through the bcm???