It sounds like you have a bad ground or a relay is getting weak. to be sure lets test the voltage at the headlight connector (yellow wire) with the lights on, it should be a little over twelve volts. here is a guide to help us get started and the headlight wiring diagrams below so you can see how the system works:
Please run down this guide and report back.
Images (Click to enlarge)
Monday, January 14th, 2019 AT 10:46 AM