How Many Circuits are Supported by the Optronics 7 Pole to 5 Pole Flat Wired Adapter # A57WB

Question:

Hooked it up to my truck and trailer and the back up lights come on all the time. the current broken one I have does not do that . also this is sold as a 7 pole into 5 flat pole , my old one has all 7 connectors there yours only has 5 on the pole end that is meant to be 7.

asked by: Peter A

Expert Reply:

Thank you for your recent purchases from etrailer.

The Optronics 7 Pole to 5 Pole Flat Wired Adapter # A57WB that you purchased is intended to allow a tow vehicle with an RV-style 7-way blade type trailer socket to connect to a trailer that uses a 5-pole flat type connector. The linked article on trailer wiring shows these and other connector types commonly in use.

The 5th wire on a typical 5-pole trailer is usually blue in color and is there to carry signals for electric trailer brakes. It is possible that your trailer is wired differently and this could be the reason for your trailer reverse lights coming on. It could also be that there is corrosion within the trailer's connector that is causing two different circuits to be bridged together. Check the trailer connector that plugs into the adapter's 5-pole side; look for any corrosion or discoloration and clean as needed.

The 7-pole plug on the Optronics adapter does only have 5 contacts installed. This is intentional since the 5-pole flat connector can support only 4 circuits plus the ground.

expert reply by: Adam R