The ammeter is fine, as far as I know. The warning light glows when appropriate. With previous regulators (before the last one) the meter fluctuated back and forth wildly just before the regulator died, then settled comfortably in the negative zone.Not sure,,, this is a long shot,,, but maybe someone else can chime in...If the wiring is correct. The Alt. Meter in our cars is wired in Series, Not Parallel, Have you noticed anything Going wrong with the meter inside the Car? did that smoke too... Over amps can short that meter out. Just saying...