How to Make a 9-Pin to 7-Way Adapter

Question:

I am needing a wiring adapter from a pollack 9 pin on the trailer to the 7 pin plug on my 2008 Chevy Duramax. This for a one time use on a borrowed trailer so I dont want to rewire either truck or trailer. Thank you.

asked by: Loch A

Expert Reply:

To adapt your 9-pin trailer plug to work with the 7-way connector on the truck, you would need the 9-pin vehicle side connector that you referenced, part # R9CB. A length of 7-wire cable # DW04914-1 from the 9-pin would be tapped into the relevant circuits behind the 7-way, with the two remaining terminals being connected as needed. For a more temporary install, the 9-way R9CB could be temporarily attached to the truck, with a length of # DW04914-1 wired to the appropriate terminals on the rear of the connector. Wire the other end of the cable to a 7-way trailer end like # A7WCB, which would plug into the 7-way on the truck when needed. The remaining two terminals on the 9 pin would be connected as needed.

expert reply by: Jameson C