Tachometer Problems

What would cause the tach to only "come on" at above 2000 RPM's?
Mike

Check the fuse block under the hood. Make sure the contacts for the fuses are free of corrosion. If they are corroded, get some emery cloth from the auto parts store and clean up the contacts.

Thanks, but I've tried that remedy already, including cleaning all the fuse contacts. Is it possible the Timing Computer is the culprit?
Mike