Firstly whilst driving my drivers door alarm was going off on the dash when it was clearly closed,

prior to this first fault ive installed some angel eyes and replaced a headlamp bulb as it never work (damaged from installation)

starting to think maybe earth fault.

then power steering went, fans, cd player and the display was flickering. I was advised this was my alternator

charged my battery to full, and the same happened again agter about 5mile down the road the with lights on. battery light on dash also.
replaced alternator today by mechanic for refurb replica
when on the test drive - SAME AGAIN!
possible battery fault?
battery reads 12.5v but when connected to car terminals and the engine is running drops to 9vlts ish.

HELP!!!!!