Battery/Electrical Issue 2021 Sprinter 35bh

[JSCampinginBama]

Hello everyone! I recently purchased the 2021 keystone sprinter 35BH. The people I purchased it from had been living in it full-time for over a year. I got it home no issue. As I was backing it into the garage, the hitch grabbed the emergency electrical brake and then engaged. I pushed the pin back into the box and it stopped. Two days later I was out checking out the rig and the propane detector was sounding. I then noticed that I smelled an electrical burning smell. I checked the front compartment and the battery was incredibly hot. I saw there was a blue insulated wire coming from the battery that had most of its insulation burned off of it. I immediately disconnected the battery and the shore power. I contacted my electrician who tested the shore power for accuracy. I later took the battery to be tested and found it to be unable to hold a charge. I have ordered a converter and purchased a new battery. I will rework the wiring and install the battery and converter.

Does anybody have any idea why this occurred? Does anyone have any recommendations as to anything else I should do further? Do you think that the emergency electrical brake engaging had something to do with this? I appreciate any input.

[bobbecky]

Yes. That blue wire could be the power source for the emergency breakaway system. You probably should verify that and if it is, replace the wire and probably replace the breakaway switch too. The breakaway power is usually not fused, so don't think you need to add it. The design is for emergencies and you don't want a blown fuse to disable the system and not have it ready to stop the trailer.

[JSCampinginBama]

Originally Posted by bobbecky

Yes. That blue wire could be the power source for the emergency breakaway system. You probably should verify that and if it is, replace the wire and probably replace the breakaway switch too. The breakaway power is usually not fused, so don't think you need to add it. The design is for emergencies and you don't want a blown fuse to disable the system and not have it ready to stop the trailer.

Thank you! Any idea why the wire would have burned/melted like this?

[chuckster57]

Welcome to the forum

As long as you put the pin back in right away, I doubt the break away caused your issue. How old is the battery, was the water level checked in the cells?

I wouldn’t replace your converter unless you tested it and it isn’t charging, a HOT battery tells me it is most likely working. Any idea where the BLUE wire went from the battery?

[chuckster57]

Break away is usually powered from the battery but connected at the junction box, then connected to the blue wire in the junction box.

Its sole job is to energize the brakes if the trailer comes unhooked and the umbilical cord pulls out of the 7 way socket. I’m real curious to hear what the blue wire went to from the battery, as I don’t think that’s “factory”.

[Kirk's Keystone Outback.]

Originally Posted by JSCampinginBama

Hello everyone! I recently purchased the 2021 keystone sprinter 35BH. The people I purchased it from had been living in it full-time for over a year. I got it home no issue. As I was backing it into the garage, the hitch grabbed the emergency electrical brake and then engaged. I pushed the pin back into the box and it stopped. Two days later I was out checking out the rig and the propane detector was sounding. I then noticed that I smelled an electrical burning smell. I checked the front compartment and the battery was incredibly hot. I saw there was a blue insulated wire coming from the battery that had most of its insulation burned off of it. I immediately disconnected the battery and the shore power. I contacted my electrician who tested the shore power for accuracy. I later took the battery to be tested and found it to be unable to hold a charge. I have ordered a converter and purchased a new battery. I will rework the wiring and install the battery and converter.

Does anybody have any idea why this occurred? Does anyone have any recommendations as to anything else I should do further? Do you think that the emergency electrical brake engaging had something to do with this? I appreciate any input.

My previous battery was apparently failing to the point of no return while I was at work, because when I got home, there was a strong odor of sulfuric acid and the digital volt meter I installed in front was higher than ever, of course the battery was extremely hot. I routinely checked the water. It failed after 3.5 years, usually plugged into shore power. Just a thought.