I have an issue with my internment part of my wipers they don't work
The wiper delay timer for that truck is in the wiper motor. I have seen the switch go bad. But more often than not it's the motor itself. There is a slim chance you could have a wire harness fault. But this is very rare.
The system is so difficult to diagnose due to the complex wiring and control module. That even the dealer just swaps parts until the problem is found. But they do have a stock room full of parts they could try.
Search Chevrolet Silverado 1500 Questions
Chevrolet Silverado 1500 Experts