You have, on the back of the alternator, a plug with three wires (these go to the voltage regulator on the fender, passenger side, rectangular box) and the hot wire, which has a separate connection. There is also a ground strap (usually frayed off by now) from one of the through bolts to the bracket or engine mount.

If you tied the three wires together, you are grounding the rotor, and will drain the battery. Certainly, the light will go out, since it is no longer connected, but now the alternator isn't, either.

The usual reasons the light won't go out are missing fan belt or dead diodes or brushes. If you can still re-connect the wires to where they were (each wire has a differernt color), you can take it to a battery shop and have them test it. You might just have a loose belt (if so, I can give you instructions on tightening it), but you may also have a bad alternator. It is, after all, thirty years old! You must re-connect the wires properly to get the alternator to work.

Peter

The alternator is on the passenger side.

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!