How to Hook Up Two Trailer Batteries On a 1994 Aljo Travel Trailer


I took the two batteries off my 94 aljo and stored them all winter and when I put them on the trailer.I forgot which wire goes to which barttery and neg. or positive? I have 2 trailer batteries and lot of wires? help!

Expert Reply:

Your system could be 12 volts with the batteries wired in parallel or it could be 24 volts which requires wiring in series. I will provide a short explanation for you. Let me know if other wiring is involved, if so further information will be required to help with wiring the batteries on your trailer. If you can give me a complete trailer description along with the type of electrical hookup you are supposed to use I will be glad to help with the wiring.

If you have a 12 volt system you will need to wire in parallel, run the positive cable from the RV to the positive post of the first battery and then run a positive jumper cable to the positive post of the second battery. Next do the same for the negative side. Negative from RV to negative on first battery and a negative jumper to negative post on second battery.

If the system is 24 volts then run the positive wire from the RV to the positive post on the first battery and then run a jumper from the negative post on the first battery to the positive post on the second battery. Now run the negative cable from the RV to the negative post of the second battery. This is wiring in series and supplies 24 volts for a 24 volt system.

expert reply by:
Robert G

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