Thursday, June 28, 2012

How to Connect Trailer Wiring: 2003 Chevy S-10 Pickup

How to Connect Trailer Wiring: 2003 Chevy S-10 Pickup

  • The Plan: Borrow a tent-trailer and go camping
  • The Problem: No hitch and no electrical connection on my pickup
  • The Process: Install a hitch and an electrical connection compatible with the trailer

Step One - the easy part: install a hitch.

The 2003 Chevy S-10 bumper is completely adequate for hauling a tent-trailer, at least the one I borrowed from a friend. The bumper is labeled with two weight limits:


The single-axle Coleman tent-trailer does not exceed these limits.

The trailer required a two-inch diameter ball hitch. My bumper was pre-drilled with a half-inch hole. I purchased a ball hitch rated at 3500 pounds, with a half-inch threaded stem. It fit perfectly in the bumper.

Step Two - the harder part: install wiring harness.

The Chevy S-10 pickup uses a snap connector to join the rear lights wiring with the electrical system. This location is a good place to splice in the trailer wiring connection.

Locate the connector under the rear of the pickup, on the driver-side, near the corner where the bumper joins the bed of the truck.

Step Three - Uncover the wiring

Unwrap the wiring on the bumper-side of the connection, allowing you to see each individual wire.

There are five wires coming from the connector, each a different color.

Step Four - Identify the wiring

Use a sharp-tipped electrical probe to identify which wire activates which light.

The red clip of the probe connects to the ground or common connection of the system, which could even be the steel frame of the pickup chassis.

Here the probe is connected to the frame of the chassis and the sharp tip pierces the first wire, the dark green. To provide a backing pad and avoid piercing a finger, use a stiff piece of cardboard.

While piercing the dark green wire, have an assistant activate the right turn signal. The probe should respond by flashing, indicating it is piercing the wire that carries electrical current to the right turn signal lamp.

Repeat with each wire in turn, noting how the probe responds with each activation of a function. You should end up confirming the following diagram:

  • Dark Green: Right Turn
  • Light Green: (Unused)
  • Solid Brown: Taillight
  • Yellow: Left Turn
  • White-striped Brown: Taillight

Step Five - Splice in the trailer wiring

Use a couple feet of four-wire flat ribbon wiring harness, with snap-fit splicing connectors.

Splice the brown wire of the trailer ribbon to the solid brown wire of the truck wiring.

Use pliers to force the metal tab into the connection, electrically joining the two wires.

Finish the splice by snapping the plastic tab in place.

Now, splice the same brown wire of the trailer ribbon to the white-stripped brown wire of the truck wiring. This connects both left and right taillights to the one brown wire of the trailer harness.

Splice the yellow wire of the trailer harness to the yellow wire of the truck wiring.

Splice the green wire of the trailer harness to the dark green wire of the truck wiring.

Splice the white wire of the trailer harness to the black wire connected directly to the steel frame of the truck chassis. This is the ground or common connection for the entire electrical system.

The ground wire screw attached to the steel chassis is also a good place to clip the electrical probe for testing.

Step Six - Test the integrity of each splice

Probe each wire of the connected trailer harness while an assistant activates the turn signals and taillights. Taillights are activated by turning on the vehicle's parking lights. The probe should respond by lighting up when the appropriate wire is probed.

The ground wire connection is tested using a multimeter set to measure resistance: RX 1K Ohms.

The multimeter is connected inline with the ground wire on the truck chassis and the ground wire of the trailer harness.

Set the multimeter selector to measure resistance. Connect one lead to the ground screw of the pickup chassis frame. Connect the other lead to the bare copper wire at the end of the white wire of the trailer harness. If there is a good connection the multimeter will indicate nearly zero ohms of resistance, swinging the indicator needle all the way to the right.

Step Seven - Secure the wiring

A good way to secure the wiring is to enclose the trailer harness in protective cable covers. Add zip ties to secure the wiring to the frame.

The licence plate is illuminated by two small lamps. One of the lamps can be removed, allowing the trailer harness to be fed through the hole. Zip ties will keep the wiring in place.

The trailer I expected to borrow required a six-pole male round connector on the pickup.

The pole positions are standardized, making it easy to connect to the four wires of the trailer harness.

  • White: Connect to pole labeled GD
  • Brown: Connect to pole labeled TM
  • Yellow: Connect to pole labeled LT
  • Green: Connect to pole labeled RT

Before connecting the wires to the plug, be sure to slip the protective rubber boot over the harness. Consider using an underwriter's knot to prevent stress on the connections.

Another helpful technique is to tin each lead with solder. This helps provide a better contact with the screw-in pole connection.

With all four leads tinned, insert each in its correct connection and tighten the binding screw.

Slide the rubber boot up over the terminals.

The existing holes may allow the connector to be fastened, but be prepared to drill holes in the bumper to fit.

After the connection is mounted securely to the bumper, add more zip ties underneath.

With the connector secured inside and out, and the hitch bolted down, you're ready to hook up to the trailer and travel on down the road!

Images provided by the author, Milt Reynolds, Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 Unported License.

Thursday, June 14, 2012

Dummies, Electricity, and Spray Foam Don't Mix

Dummies, Electricity, and Spray Foam Don't Mix

This is a guest post by my friend, Rebecca Hundt. I had no idea she was such a talented writer! She's graciously allowed me to post it to my blog. Misery loves company and her story sure brightened my day! Thank you, Rebecca!

I hate Scentsy air fresheners. They're made from petroleum solvents and are toxic. They smell gaudy, and I'm allergic to perfumes. They give me a headache and exasperate my hay fever.

My downstairs neighbors have a different opinion. They love the stuff. They love Scentsy products so much that they want to share it with the world. Their favorite scents spill out of their apartment into the stairwell and parking lot.

It also seeps into my apartment.

Building codes state that apartments must be individually sealed as a firestop. However, these aren't well-built buildings. Odors pass through cracks and holes in the walls and into the shared spaces behind the drywall. Volatile organics such as perfume rise as they evaporate. I'm on the top floor and this is where the smell collects.

I complained to the manager. I told her how I couldn't open my windows or use my balcony. I also told her how the smell seeps in, even with the doors and windows shut. She looked at me as if I were a crazed hypochondriac. After all, she's a Scentsy Product Sales Associate, and she would never sell a toxic product to the people in apartment D204, her best customers. How can something pretty be toxic?

Seeing that I would get no help from her, I set about smell-proofing my apartment. I caulked around the windows and doors. I sealed the cracks in the drywall. I got a carbon air filter for my central air system. I bought a can of aerosol spray foam and sealed the holes in the drywall under the sinks from the plumbing.

I was proud of myself. The smell was almost gone. There was only one source of smell left: the outlets.

Armed with foam and a screwdriver, I removed the outlet plate. Sure enough, there was a gap between the drywall and outlet box, so I sprayed. The nozzle straw fell off the can and foam sprayed everywhere. The wet foam expanded in the entire outlet box and hit live wires. Thankfully, the circuit breaker tripped, and I wasn't electrocuted.

But I did panic.

Visions of electrical fires flashed through my mind. Eviction, fines, and costly repair bills followed. Worse of all, I'd lose my deposit.

I ran to the electrical panel and turned the power off to the outlets. I grabbed my vacuum cleaner and sucked out the wet foam with the hose attachment. Not all of it would come out however, but I did the best I could. I put the plate back on and turned the power on. I plugged a fan into the outlet and turned it on.

Nothing happened.


I turned the power back off and pulled the plate from the box and vacuumed again. The foam was now almost dry. Again I put it back together and turned the power back on.

Nothing happened.

It was time to admit defeat. I’d have to call the manager to get it fixed. But first, I'd have to hide the evidence of my spray foam stupidity.

I turned the power off and pulled the entire outlet out of the box. Using an old toothbrush I brushed off what I could of the remaining foam...a task easier said than done. It was in nooks and crannies, under wires and everywhere else. I couldn't get it all, but most of the evidence was gone. I put it back together and turned the power back on.

I went to the kitchen sink to scrub foam off my hands. As I washed, my eyes landed on the outlet above the counter, specifically the TEST and RESET buttons of the GFI, the Ground Fault Interupter. The RESET button was tripped.

I then realized that the foam had indeed shorted the circuit, tripping the breaker as well as the GFI, preventing my electrocution.

I hit RESET and sure enough, the outlet worked.

I'm not sure if dry spray foam is flammable and "electronically safe". The instructions on the can were unclear on what to do in this situation.

My apartment hasn't burned down...yet. My deposit is safe...for now.

My new vacuum cleaner, however, has a clogged filter.

And I can still smell that damn perfume.