Thats what I do is to look on the BATTERY CASE and find the STAMPED word NEG or SYMBOL '-'. Then make sure the cable wire that runs from FRAME GROUND that should be just inches away from the battery goes to the NEG battery connection. In your case it should be the WHITE ONE but need to check to be sure...
I'm like you on not knowing which colors work anymore... In the RV WORLD POSITIVE is suppose to be a BLACK COLORED WIRE and the NEGATIVE is suppose to be the WHITE WIRE.
But we all have grown up with the automotive BATTERY colors where RED is POSITIVE and BLACK is FRAME GROUND.... So you can see how easy it is to do it wrong hehe...
If you have already done it wrong and it sparked then you will have to look for two REVERSE POLARITY PROTECTION fuses in the 12VDC Distribution panel and also an IN-LINE FUSE in the Battery Cables that will be very close to the battery connection. All three of the fuses will blow immediately when you spark it. The newer trailers are starting to use a resetable Circuit BREAKER now in place of the IN-LINE FUSE that is close to the battery connection.
NO HARM DONE except looking for the fuses...
Roy Ken
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