Toyota Repair: Electrical problem, alternator output, ground cable

Question
1993 Toy. P.U.  22R  Automatic transmission
Batt. light and the brake light (idiot lights) came on the dash.  I checked the Alt. by pulling the negitive cable while the veh. was running and it caused it to die.  I had the alt. rebuilt, put it back on the trk. and the lights are still on.  I drove the veh. thinking the batt. needed to be charged by the alt. but found it didn't help.  The veh. lost power like it wasn't running on all cylinders.  The speedomiter needle started jumping around when I turned on the turn signal indacating a short.  I'm thinking the ground cable.  What do you think.

Answer
Either the rebilt alternator is not cgarging the battery or the battery itself has a problem and won't accept a charge, try another good battery or have the alternator output tested, you can get a pretty good idea if is working properly by checking the voltage across the battery with the engine running, it should read between 13.8-14.5 volts.

If both the battery and alternator are good I would start looking at a wiring problem, pssibly a bad connection at ground or the battery terminals.