Alright, so I have an 1989 accord.
left outta town for a weeek and when I got back and started it up my battery light was on and my battery was not being charged. I can jump start it and keep it running connected to a car and with a charged battery in it, but it will eventually drain the battery and kill the car. I replaced the alternator although o reilys said it was good. Im guessing that it is either a problem in the grounds or just in the wire harness itself, im just nit sure if there is a fusible link somewhere in the harness. I also took a look at what I believe is the ground wire from the alternator and it looks as if it was spliced and shrink wrapped and is now corroded or shorted.

 

Charge the battery fully or get a new one. Start the car. Disconnect the negative battery terminal. If it dies its the alternator. If it stays running reconnect the negative and disconnect the positive. If it dies its the battery.

Thats an old quick way to trouble shoot to know for sure.

Assuming it ends of being the alternator "" and its a new one testing good. Then go after the wiring. One big hot from battery to alternator. One ground either on it or utilizes the engine ground. Then youve got a plug or two for the regulator. Check for power at these with engine off key on one or a few should be either 5v or 12v. If no power to any of the regulator plug plugs" then check fuses every one*...all else fails refer to wiring diagram and just run new wire leaving old stuff where it is.