on board charger

[moronehead]

I bought a 96 Scout last year and finally put a bow mounted trolling motor on it. I got 2 trolling motor batteries plus starter. The boat came with a Guest 3 bank charger. Seemed like only the starter battery bank ever worked, now nothing, no lights come on. No voltage to any of the leads but continuity shows through all 3 lead pairs. They give a lifetime waterprooof guaruntee but Im not sure if I want to pay postage for nothing. Any way to further test? Any help would be appreciated.