Installing Trailer Wiring Harness on a 2004 Ford Focus
Question:
I have purchased a wireing harness with a converter. It is for my 2004 ford focus 4dr sedan. I need to see a diagram with instructions about how to and where to hook this up.
asked by: James L
Expert Reply:
It looks like you have purchased wiring harness # 18252 which is correct for a 2004 Ford Focus. This vehicle does not require a converter because it has what is called a combined lighting system. This means the brake lights and turn signals are combined onto one circuit. This is the same way most trailers are wired.
You will use the included circuit tester to tech the wires behind the tail lights on the vehicle. Starting on the drivers side, where you will be attaching 3 of the wires, first look for the wire that shows power when the left turn signal is activated. It attaches to the yellow wire.
Then look for the wire that shows power with the running lights on. Attach the wiring harness brown wire to it. For the white wire, find a clean bare metal surface to attach the white ground wire.
Then you will run the green wire to the passenger side. Attach it to the wire on that side that carries the right turn signal. To test the wires the included circuit tester should be all you need unless you own one that you would rather use.
I have included a link to a video showing a typical installation on a 2003 Ford Focus. It is a different year but the testing process will be the same. You must test the wires before making any connections because you cannot always go by wire color on a vehicle.
Products Referenced in This Question
4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- 6 Feet Long
- Universal Fit
- 4 Flat
- Tekonsha
more information >
Product Page this Question was Asked From
4-Way Flat Trailer Connector w/ 60" Harness and Wire Taps
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- 0 - 5 Feet Long
- Plug and Lead
- 4 Flat
- Tekonsha
more information >
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