What is the extra yelow wire on a 7 to 4 adapter? All I can find is for auxillary power. What is that? Do I need this to be hot? Is this what charges my RV battery? CAn I leave unhooked? Any help would be appreciatted. Thanks!!
asked by: Matt
The black wire is the 12V hot power source that is usually used to maintain a trailer battery.
The yellow wire, in some cases it is orange or purple, is for the center post which is usually wired for reverse lights or a reverse lockout on a boat trailer.
If you do not need a reverse circuit, you can just tape the yellow wire up and out of the way.
expert reply by: Patrick B
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Product Page this Question was Asked From
Single Function Adapter
1 Foot Long
Plug and Lead
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