Voltmeters are wired up to positive and negative (ground), and check the available voltage.
Ammeters measure current flow through the ammeter, and are wired between the positive source, and the items being powered by that source.
Using the voltmeter wires to hook up a ammeter, will short out the battery. You've got a blown fuse, or burnt wire. Unhook the ammeter, replace the fuse, and the other gauges should work again.
Off the subject, though....
What the difference is, between a mechanical voltmeter, and a electrical voltmeter. Both are electrical devices, aren't they? Is it the difference between measuring the voltage across a resistor with a analog gauge, as opposed to measuring the voltage with a transistorized circuit, which feeds a voltage gauge?