This could be a problem with the steering control module. This module contains the horn switch, the multi-function switch, and the speed control switch. If this module fails all of these and a couple more circuits will not work. I have included in the diagrams below factory diagnostic troubleshooting guide and removal and installation instructions for the steering wheel control module. Please go through them and get back to us with what you find out.
Images (Click to enlarge)
Friday, March 29th, 2019 AT 10:26 AM