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Trailer Lighting Replacement Guide

Trailer Lighting Replacement

Faulty lighting is one of the easiest ways to get stopped on or off the water. The simplest answer to lighting problems on your 20+ year old trailer could be a complete replacement. Trailer lighting replacement is a simple self maintenance task that is well worth the investment.

The following is an instruction for installing replacement of lights on a 24 ft tandem axle EZ loader trailer (over 80" wide).

The job is easily done by one person in 2-3 hours with wire strippers, wrenches, wire nuts and electrical tape.

A. Wiring from Tow Vehicle

The color for wiring from the vehicle to trailers is standardized as follows:

WHITE is the ground wire. The white wire from the trailer connector will be terminated to the tongue of the trailer using a crimped ring connector, and all light circuits will be grounded similarly.

YELLOW is the left turn signal and stop wire.

GREEN is the right turn signal and stop wire.

BROWN is the running light wire (for the tail lights, amber side lights, and left rear license plate light.

B. Wiring the Trailer

1. Cut existing wiring at the lights and remove the old lighting fixtures. If wrenches won't loosen rusted nuts, try a hammer and /or hack saw.

2. Use the existing wire to pull the new wires through body of the trailer. Leave at least 12" from the connector extending out of the tongue of the trailer. Attach the WHITE wire from the trailer connector to the tongue of the trailer using a crimped ring connector. Make sure the is contact surfaces are free of rust and paint.

3. Cut off the existing connector and attach the green and brown wires on the trailer to the green and brown wires on the new harness connector. Tape down the free ends so it doesn't hang up as you pull it through the right side of the trailer tubing.

4. Repeat for the left side with the yellow and brown wires

C. Installing the Red Tail Lights (running, turn, and stop)

1. The LEFT rear light has an open bottom with the license plate light. The RIGHT rear light has a solid bottom.

2. The mounting bolts slide into channels in the molded plastic of the light back housing. Insert 2 bolts to align the lights with the mounting bracket. Sand or wire brush to expose bare metal on the light mounting bracket.

3. Route the wiring in the channel in the molded housing, Attach the light placing ground wire (WHITE) lug between the light housing and the bracket. Secure the mounting nuts until the lock washers are compressed. On the LEFT side, the license plate bracket goes between the light and the trailer bracket.

4. Cut harness wire to length, strip wire ~3/8", and attach with wire nuts. For the RIGHT light this is BROWN to BROWN, GREEN to GREEN. Apply electrical tape over wire nut, coil any excess and tape.

5. Repeat for the LEFT light this is BROWN to BROWN, YELLOW to YELLOW

6. Consider a grommet or extra electrical tape wherever the wire enters the trailer body / tubing.

D. Installing the AMBER Side Marker Lights

1. The amber running lights should be installed as far forward as possible.

2. The mounting bolts slide into channels in the molded plastic of the light back housing. Secure the nut until the lock washer compresses. Sometimes they can also be mounted with sheet metal screws.

3. Route the brown wire through a convenient hole in the trailer tube.

4. Splice/ Join the wire as follows: Cut the brown wire running the length of the trailer, strip both ends, and twist both together with the light wire. Secure with a wire nut and electrical tape as before. Push excess wiring inside trailer body.

E.Testing the Circuits

1. Connect the Trailer wire connector to the tow vehicle connector.

2. Turn on the headlights. Verify the amber side marker lights, the red tail lights, and the license plate light are ON.

3. Turn the vehicle ignition ON and verify the turn signals work (L and R)on both the vehicle and the trailer.

4. Have a helper press the vehicle brake pedal and verify the both tail lights come "ON".

5. If the Lights don't work at all, check the voltage at the vehicle connector with a voltmeter. Next check the ground connections are clean and secure.

6. If any one light doesn't work, check it's connections and ground.

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