05 starting issue..electrical

Your battery is the root of all evil.

The battery has lost it's guts, probably low on fluid. That is the source of your problem--get a fresh battery and then it will likely run okay unless you have other issues. Less than about 10 volts battery don't likey and neither does fuel injection.

And you may have a short circuit somewhere that is pulling the voltage down that low, but it is likely the headlights doing that. Voltage is pulled way low and battery can't supply enough current to light them up.