Locating Power Wire for Breakaway Battery

Question:

I just replaced my 7way on my trailer it has a yellow wire for auxiliary power and my breakaway has a black wire said to tow vehicle for power. Do I hook them together

asked by: Daniel

Expert Reply:

If the yellow wire has constant 12V power when connected to the tow vehicle, then you can use it to charge your breakaway battery.

If the yellow wire doesn't have constant 12V power then my guess would be that its tied to the center pin of the trailer connector which is typically used for the reverse lights.

If this is the case then you will want to splice into the wire that is in the 11 o'clock pin when looking at the face of the trailer connector, this is usually a black wire, which has the constant 12V you will need to power your breakaway battery.

expert reply by: Jackie C