Toyota workshop manual, circuits at end. (It will also help an auto electrician if you end up with one)
https://dl.dropboxusercontent.com/u/831 ... rm399e.pdfThe gauge fuse also drives a relay which switches power to the windows so the original failure looks like a single failure.
If the alt fuse is gone, then most circuits will stop working, including engine control, lighting plus all on the original gauge fuse.
The particular thing that normally blows the alt fuse (It is 100A !) is a short circuit to ground on the large output terminal on the back of the alternator. A faulty alternator could also cause this, it could also blow the gauge fuse as this feeds one of the low power connections through the alternator plug.
As above, inspect the wiring loom closely, especially in the engine bay and particularly at the back of the alternator. Check for signs of overheating / melting. Check for signs of insulation damage if it's rubbing against something hot (exhaust) or moving or just metal.
If you find fuses blowing, don't ever replace with a higher value as this will just burn out the wiring loom if the problem is not resolved. In this case, I would try unplugging the alternator and disconnecting the large (M6 stud / 10mm nut) output connection and insulating the crimp ring (don't let it touch metal or it will blow the alt fuse)
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If at first you don't suck seed, try drier grain.