Electrical issue on 2010 Launch 22v

Two weeks ago we purchased a 2010 Supra Launch 22v and have put 14 hours on it. In the process of boating on Saturday we lost power to the blower, horn, bilge, stereo, heater, accessory lights, courtesy lights, docking light, navi lights. The instrument gauges, Supra Vision, and ballast pumps all work and the engine starts. The Main thermal circuit breaker was tripped and I've reset several times. I've also checked all the fuses, reset each, but none of those were tripped. The only issue that I was working through was the stereo amplifier was overheating and kicking into thermal shut off mode, not sure if that would have anything to do with all the other items. I'm at a loss on what the issue is and I don't have a multimeter on hand, appreciate any suggestions for trying to remedy.

I’ve switched the thermal circuit, didn’t fix the issue. I’ve checked the batteries, battery 1 at 12.5 amp and battery 2 at 3.7. I’ve rechecked the fuses, all good. Does anyone know where I can get info on the boat’s two PDMs? Or, even where to source them online?

I removed secondary house battery, charged for 12 hours. It went from 3.7 volts to 5.9. Bad battery and no wonder none of the electronics through the buss bar were working. Purchased new battery and everything back to normal. The boat broker I purchased it from said the batteries were new. He was right, they were put in last August, but the previous owner had to have left the battery switch on. Lessons learned.

Question sir, I have a 2012 Launch 242 and experiencing the same issue. Did you ever get this resolved by chance?