Okay, so they fade on/off in a regular cycle? Does this happen when you just turn on the key or does the engine need to be running? As a test you can go to the under-hood fuse box and look for the ABS module fuse and remove it. If the problem is in the module or related to it the ABS light should change. If it does but the CEL still acts like a disco then it is more than likely a cluster error. Ford uses the cluster to do a lot more than just the gauges so anything can effect them. The attached diagram shows the possible fuse locations depending on the build date. Ford made a few changes depending on model and engine. The cover should tell you which it actually is.
For the brake pulse, I would pull the wheels and then the rotors, clean off the inside of the rotor and the surface of the hub, then carefully tighten the lug nuts to torque and see if it stops, a tiny bit of rust or dirt on that mating surface will cause the rotor to have serious run out at the friction surface.
Images (Click to enlarge)
Monday, February 11th, 2019 AT 2:05 PM