Converting an Existing 9-pole Trailer Connection Plug to a 7-Way Connection
Question:
I am getting an older trailer with a 9 pole connector. My truck has a 7 blade. Is there an adapter I can buy that will handle this? I am not an electrician, so looking for an easy fix for this. Thanks!
asked by: Mike F
Helpful Expert Reply:
We do not supply a 9-pole to a 7-blade connector converter, but you can definitely convert your existing trailer connector to a 7-way blade connecter that will work with your truck.
To do this you will need a replacement 7-blade connector like # PK12706. You will then disassemble the existing trailer connector and install the 7-way blade style connector. When you take apart the 9-pole connection point the functions should be labeled, and you will want to match up functions to the 7-way not necessarily match color for color. You may want to use ring connectors to connect the existing wires on your trailer cord wire to the new 7-way connector plug, like the # 44-5310A and # DW05702-1.
Please connect the wires on your 9-pole to the corresponding functions on the 7-way connector plug according to the diagram that I have included. Note that there are 2 wires that will not be connected the gray auxiliary, and orange refrigerator or stop, please terminate these and wrap up with tape.
I have included a diagram showing the configuration of the two plug styles, and a short installation video of a 7-way replacement plug that shows the same procedure that you would follow for replacing the 9-pole connection on your trailer.

Products Referenced in This Question
Ring Terminal - 12-10 Gauge Wire - 3/16" Ring ID
- Wiring
- Wire Connectors
- Ring Terminals
- 3/16 Inch Diameter
- 12-10 Gauge
- Flint Hill Goods
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Ring Terminal -16-14 Gauge - 1/4" Ring ID - Qty. 1
- Wiring
- Wire Connectors
- Ring Terminals
- 1/4 Inch Diameter
- 16-14 Gauge
- Deka
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Pollak Black Plastic, 7-Pole, RV-Style Trailer Connector - Trailer End
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- Plug Only
- 7 Round - Blade
- Pollak
more information >
Product Page this Question was Asked From
Pollak Heavy-Duty, 7-Pole, Round Pin Trailer Wiring Socket - Vehicle End
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug Only
- 7 Round - Round
- Pollak
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