Sorry guys been putn in time on the down time bench and re-chargn my batteries,best i can tell just now is that gtow69 is on the money,further to that could you also mark the wires on the ammeter and remove them then check that you have a circuit through it and not to ground (body of the truck).One issue i have all ways had with ammeters is that although they give a better indication of current flow they are generaly un protected (fused) and once upgraded from a generator (approx 20-30 amps output) to an alternator (any where from 35-140 amps output)the potential for the insulators on the bolt posts at the rear of the ammeter to fail thereby allowing it to short out on the body of the meter are very real,this is only a problem due to the fact most automotive ammeters are only good for approx 60 amps,so if you have to jumpstart your truck due to a flat battery, once the alternator commences charging it will have a big output(nearly max output) until the regulator tappers it off if the said insulator's hold up all is good if not,well you don't want to know if not,i wish i could just drop in and do the repair's for you any chance i get to spend "quality time" with a truck is o.k. with me.good luck and don't hesitate to get in touch just bear in mind im half a world away and i work shifts so some times you get lucky other times you don't. just on the jumpstart thing it is o.k. to jumpstart but it is a good idea to leave both trucks linked for a few minutes to allow the regulator to tapper off.Hope this helps.
