Was it flashing with some sort of pattern,if so prob. clutch assy,if flickering/no pattern to it could be wiring fault/rubbed thru somewhere.
I`ve seen the pins corrode at the 3 pin connector & wiring rub/break over the plastic cover on top front of engine.
Squeaking is usually just the belt getting worn.
Check the belt auto tensioner above alternator though, the bearing fails & throws the belt off which can then jam behind P.A.S pump pulley & fill alternator
You can usually see when its on its way out cos belt starts running towards front of pulley & there`ll be a "shiny" area where it used to run.Belt should be level with rear edge of pulley thereabouts.