what could be wrong?

I have a VS commodore series one, the car will run but only for a short period of time, as soon as it is turned on the battery light switches on, after a short distance the Engine light and ABS light turn on, the car will continue to stay on but it loses its responsivness. What could it be?

check that it is charging
failing that pull codes from computer

Yeah cheers, ive changed the altanater, leads, plugs and now the car will drive for a short period of time and the engine light comes up with battery light, ABS lightand then i lose almost all power, and it keeps draining the battery what else it could it be? I havnt checked the computer codes yet im unsure how to do this any help would be great.

thanx for your help, ended up taking to a mechanic turns out it was the alternator capacitor.