ok ask a hard question get a hard answer.Logical steps to take..Start with a fully charged battery .When I say fully charged don't use a 4 ah charger for a couple of hours and think that because it starts the car it's got to be fully charged ...it's not.Get a multimeter,set to dc volts.measure battery volts .12.? volts .turn on ignition.Make sure you have battery/charge light working in the cluster.yes ? start the car.make sure battery light goes out.Check volts at battery:13.8-14.6 is acceptable.Check volts at the big wire on the alternator should be same or higher..Point 2 of a volt is ok.Turn lights and a/c on.recheck volts if the difference between battery and alternator is point 5 of a volt you will need an extra wire run between bat & alt.forgot to mention you should rev the engine while doing these tests.Make sure battery treminals are clean and that you do not have a slipping fan belt.Any questions?Feel free.Cheers Kevman