I was wondering if anyone knows why, my inside lights on the dash dim a little when I step on the brake or roll up the window. I mean the dimming is very very minute but I was wondering if they all use the same fuse.

 

your battery is weak and will need changing soon

 

That is what I thought but its been doing this for over 2 years on the same battery. Never had trouble starting.

 

altenator keeps recharging it.. but it probably is recharging to 70% or maybe less.. so sooner or later it will decrease till it can't be recharged anymore

 

If the alternator only charges 70%, is the alternator's fault or is it the battery. Do I need to replace both? Chances are I'll keep driving till one or the other dies

 

no if your altenator was having problems.. you would be on the side of the road now.. its the battery..