Honda Repair: 1988 Prelude Si 2.0 4WS EFI Automatic, light battery, correct speed

Question
Good morning.  I was driving to work this morning and my charging system warning light (battery light) came on, faintly at first, then bold for the rest of the trip.  The car drove fine.

Any idea what it might be?  battery?  fuse?  alternator?  I don't know if this is related or not, but for a while now the speedometer will go down to 0, then recover at the correct speed.

Thank you.

Answer
Hello Ed.... I would check the amps on the battery to make sure its at the correct amp, it won't be a fuse, and it possibly could be the alternator if it is your car is just running off the battery and that will fry the alternator and then the car will die. The second thing that is wrong is your speed sensor located on the transmission which is failing that is why your speedometer will fluctuate.