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Trailer wiring problem on 2001 Outback

The left turn signal on my boat trailer is not working. I checked all the obvious things and found although there was power to the right side and to the running lights, there is none to the left. I have traced back the wiring to a little black box under the carpeting on the right hand side of the storage area. I didn't even know there was such a thing and I suspect it is the problem. What is this thing...it has wires from the car wiring compartment on one side and the wires to the trailer harness on the other. Is it something high tech and expensive or routine and easily replaced. If I'm wrong, what else could be the problem? I've checked all the obvious stuff like bad bulbs, corroded fittings, broken wires, fuses etc. etc. Any help/advice much appreciated. ds

Reply to
DS
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Reply to
Edward Hayes

That's an isolation box, it electrically isolates the trailer from the rest of the car and converts the two color tail/turn system of the car to the trailer's single color. Some modern cars will display false "bulb out" indications due to the trailer lights. The black box prevents that.

As someone else pointed out, use a test bulb to see if the indications going _in_ to the box are working. If not see your mechanic. If they are, replacement boxes are available from any local trailer hitch shop. The black box is usually not a Subaru part.

Reply to
Bonehenge

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