Adding an Auxiliary Power Circuit to a 7-Way Trailer Connector on a 2011 Chevy Silverado 1500

Updated 02/08/2012 | Published 02/04/2012

Products Featured in This Question

10 Gauge Wire - Blue Primary - Per Foot

(104)

$1.84

Ring Terminal - 12-10 Gauge Wire - 3/16" Ring ID

(69)

$1.33

Ring Terminal - 12-10 Gauge Wire - 5/16" Ring ID

(69)

$1.00

Ring Terminal - 12-10 Gauge Wire - 3/8" Ring ID

(69)

$1.67

Pollak Circuit Breaker - Cycling/Automatic Reset - 40 Amp - Straight Mount Bracket

(49)

$7.40

Hook Probe Circuit Tester

(60)

$12.27

Question:

I have a2011 chev siverado with hd trailor pakage with ITBC and want to hook up aux power to my trailor plug for aux battery on trailor. Has anyone done this how do you do it?

asked by: Roger B

Expert Reply:

First, use a circuit tester like # 40376 if needed, to test the 7-Way trailer connector. The 12-volt circuit will be in the 1 oclock position. If the trailer side connector pin that corresponds with the 12-volt circuit is connected to the battery on the trailer, then you will not have to change or add anything.

If it is not, you can either connect the battery to that circuit or use the auxiliary pin in the center. Again, use the circuit tester to test the center pin. It may be connected to the reverse lights on the truck. If it is and you want to change it to an auxiliary power pin, you will need to disconnect the wire attached to the center pin from the back of the connector.

You will then need to get about 25 feet of # 10-1-1 wire. Connect one end to the center pin at the back of the 7-Way and route the other end under the truck, avoiding areas that may pinch or burn the wire, up through the engine compartment and over to the battery. Then, mount a 40-amp circuit breaker, # PK54540, to the metal of the engine compartment near the battery.

Take the end of the wire you routed over to the AUX side of the circuit breaker, clip off the excess wire and save it for later. Attach a ring terminal to the end of the wire and attach it to the AUX post. Next, use the excess wire and attach a ring terminal to one end and attach it to the BAT post of the circuit breaker. Route the other end to the positive battery terminal. Once complete you will have an auxiliary 12-volt circuit on the center pin of the 7-Way.

We have different sizes in ring terminals. I have linked them for you here. Ring terminals can also be obtained locally if you need a size other than 3/16, 3/8, or 5/16.

expert reply by: Michael H