How To Tow Trailer W/ 7-way Blade Connector With 2013 Freightliner 122SD W/ 7-pin Round Connector
Question:
Read you qanda on this, great write up. I’m trying to wire my trailer to accept my semi truck 7-pin round male connector. In the qanda it showed 2 sockets to mount to the trailer PK11720 and PK12-707E along with a tail light converter 119178. The diagram shown was different from the taillight converter. it had a 4-pin. I’m trying to plug in my semi 7pin round into my trailer that only has the 7pin flat blade. The trailer is a 2020 EZ4 with 3 axles 6 brakes any clarity would be REALLY appreciated.
asked by: Michael H
Helpful Expert Reply:
I would be happy to help you make a wiring adapter to allow you to connect your 2013 Freightliner 122SD with a 7 pin round connector to your 2020 EZ4 triple axle trailer.
First you will need a female 7-pin round # PK11720 and female 7-way blade # PK12-707E. Since the 7-pin round has separate brake and turn signals but a 7-way blade has combined you will need the the 3-wire to 2-wire converter # HM48847 like you mentioned.
This will get connected to 7-way connector as follows:
Red wire of converter to 6 o'clock pin on 7-way round
Yellow wire of converter to 5 o'clock pin on 7-way round
Green wire of converter to 7 o'clock pin on 7-way round
White wire to 12 o'clock pin on 7-way round
Brown wire to 11 o'clock pin on 7-wayround
On the other side of the converter you will make the following connections:
Green wire to the 11 o'clock pin on the 7-way blade
Yellow wire to the 9 o'clock pin on the 7-way blade
Brown wire to 3 o'clock pin on 7-way blade
White wire to 7 o'clock pin on 7-way blade
In addition you are going to need run some # 10-1-1 to make one connections which is the from the center pin of 7-way round to 1 o'clock pin on 7-way blade.
Now to install the Hayes Air Actuated Trailer Brake Controller - 1 to 4 Axles - Proportional # HA100400C you will need to connect it to the air lines on your truck using air line # RM450700 which is sold by the foot.
You will need to extend the # 10-1-1 from the blue brake output wire on the controller to the 5 o'clock pin on the 7-way blade.
Lastly you will connect the black wire from the controller to the positive terminal of the battery with a 30 amp circuit breaker # PK54530, and ground the white wire from the controller.
I included diagrams for both of these connectors, and videos of the products mentioned for you to take a look at.
(click to enlarge)
Products Referenced in This Question
Hopkins Tail Light Converter - LED Compatible
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 3-to-2 Converter
- Hopkins
more information >
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
more information >
Pollak Black Plastic, 7-Pole, RV Blade-Style Trailer Socket - Vehicle End
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- Plug Only
- 7 Round - Blade
- Pollak
more information >
Pollak Circuit Breaker - Cycling/Automatic Reset - 30 Amp - Straight Mount Bracket
- Accessories and Parts
- Wiring
- Circuit Breaker
- 30 Amp
- Pollak
more information >
1/4" Air Line Hose for Roadmaster BrakeMaster Flat Tow Brake Systems - Per Foot
- Accessories and Parts
- Tow Bar Braking Systems
- Air Lines
- Hoses
- Roadmaster
more information >
Product Page this Question was Asked From
Hayes Air Actuated Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Air to Electric
- Electric over Hydraulic
- Manual Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- Indicator Lights
- Up to 360 Degrees
- Hayes
more information >
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