Normally the black are positive, and the white are negative. Check the white wires, to be sure they go to a ground on the frame, just in case someone got them crossed up.
__________________ Moderator If you're going to "regret it in the morning", sleep until noon.
2012 Jay Flight 19RD
2016 Ford F150 XLT 2X4 SC 3.5L Eco Max Tow
2010 Tundra TRD DBL Cab (Traded)
2 new fluffy Corgis, Bayley and Stanley
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