NSC we use fluke multimeters in our automotive bay ; they are very expensive, about 500$ CND for a good quality one, Id suggest you check out EBAY, its where I got one for dirt cheap I wish you luck in finding out the problem

1xAxiom ax 1.2 2xPolk Audio R30 2xMordaunt-Short 3.0 H/K AVR 225 Paradigm PDR-10 Sub HTR MX-500