1999 Adventurer - Ford v10.
I added some from LEDs - when I was installing them - I 'thought' I bumped and broke the brake differential pressure switch - so I ordered a new one (boy were those plastic pieces of threads fun to get out).
Anyways, I replaced it - and now the red parking brake light won't go off... unless I unplug the switch...
The manual says the parking brake light would stay illuminated (if obviously parking brake is illuminated) or if brake fluid is low (which it's not).
I assumed the 'yellow' brake light would be if there was a fault with the brake differential switch...