HELP - Batteries Jumped with 18 volts.

[Frantz]

While taking our MH out of storage yesterday we discovered our chassis batteries were dead even though all disconnects were used; house batteries were fine.

Called Coachnet and the first guy didn't make their 45 min. time so they sent a second. Second guy got there. He immediately attached his cables to the batteries and his welder. When he hit the power switch there was a loud "crack" from the dash area, everything went black (I had been getting dash lights after 2 hours of charging with generator), so loud I thought or windshield had blown out but the shade was also dead.

The first guy Coachnet had called showed up right then. Told him what happened; he asked what the gauge was saying the charge was and the gauge had pegged at 18. We instructed the first guy to take his cables off, got his card/name and asked him to leave.

By now we no longer have steps. New guy attached his cables, set them at 12 then increased it to 14, added a boost & we started right up.

Now we have no steps, no awnings, and don't know what other damage could have been done. We have begun a claim with Coachnet but need to continue with plans. Frankly, I'm leery about heading into the wilderness of Arizona & Utah.

We have checked the fuses we know but have found nothing wrong.

Has hidden irreparable damage been done?

Anybody have any hints of where fuses for steps & awning could be located???

Thanks all

[cruzbill]

Likley hit with 24vdc, as that is common starter voltage for heavy duty trucks (HDT). Find your 12vdc fuse panel, but I can't help you find it.
Good luck!

[nothermark]

The short answer is yes, things could be blown. Check everything. If it works you are probably OK. Good designers learn that automotive systems need over voltage and noisy power protection. The problem is new designers come on and learn the hard way. Maybe you lucked out and maybe not. Chances are good that if something did not blow then it won't die from the experience.