First I noticed that a set of three instrument lights were on: Gen, Coolant, Add Oil. I did need oil, which I've added, but the three lights are still on. I don't need any coolant.

Second, after the engine starts, I'm noticing that the Tach/Volt is still operating in Voltmeter mode.

I checked the alternator belt and it was a bit loose. After tightening it up, nothing changed. I also noticed a bit of rough vibration in the alternator while its running. It also gets hot very quickly. I honestly have never noticed how hot a normal alternator runs.

My best guess is that the alternator is going. However, why are all three instrument lights coming on together? Any experience with this?

Thanks,

 

On many Japanese cars, the alternator light is tied in with the oil pressure light, to make the problem appear more serious.

I don't have my manuals handy but I'd bet that the Gen light is tied in with the coolant light.

If your alternator is dying, it can do weird things like cause the tach to work in voltmeter mode even with the engine running. Had that happen.