So when I first got my car I noticed the headlights would flicker and the interior lights would dim when the stereo hit bass notes etc...
so I check the level of water in the battery, it's about 2" below the "UPPER LEVEL" line. So I fill it with some distilled water. I charge the battery and things seem fine.
However, after installing a larger horn, I noticed every time I beep the horn, the headlights dim, the backlighting on the stereo etc, things dim.
I go to Murray's today to borrow their battery tester. The tester tells me my battery's voltage is too high (13.2v with the engine off) and with the engine running the voltage is 14.2v. It also claims there's "Excess diode ripple voltage."
Is this just a case of a bad battery or is it my alternator? Help please.