All ActivityMost RecentMost LikesSolutionsRe: connecting "in-series" batteriesJust wanted to give an update that I was able to use my multi-meter and tracing back the wires to figure out the wiring and connect my new batteries successfully. The two white wires are ground, the red wire supplies voltage to the batteries to charge them (reads about 13.5 volts when connected to shore power) and the black wire is also a power wire that goes to the 7-way hookup. Thanks for the diagram and website link "Pianotuna". I hooked it up the way you suggested. Thanks to everyone who provided input and advice!Re: connecting "in-series" batteriesTo answer your questions, it is a 1994 Cobra Sierra, 21 ft. Batteries are 12volt, so I guess they need to be in parallel, not in series, so that already helps me, but I still need to figure out where each wire goes. Thanks for your input!connecting "in-series" batteriesThis topic has been moved to another forum. You can read it here: 27057838connecting "in-series" batteriesMy travel trailer's batteries were stolen and now that I have 2 new ones to reconnect them, but of course they were already properly connected when I bought the trailer and I never had a need to mess with the wiring before and I don't know how they were connected to begin with. Some of the wires were cut when the batteries were stolen and some were left in-tact. I can easily reconnect everything as far as having the proper tools and supplies to do so, but I don't know which cables go where. The wires coming out of the trailer are 1 red, 2 white, and 1 black...so first I need to know where each of those should be connected and then also how to connect the 2 batteries to one another in series. Thanks very much for any help and advice that you can offer!! Moved to Tech Issues forum from DIY.