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On my 1997 Mountaineer, V8, AWD, I plugged the 4-wire adapter to it and I get no power to the trailer trailer lights. Fuses look OK... any other options for easy hoop up
Any idea if it ever did work? On my 1993, the trailer wires would show 12 V but when I hooked up the trailer, the ligths did not work. Dealer didn't believe me and said my trailer was bad. After 3 trips back to them, they finally hooked up a light to the pigtail and guess what, it did not go on. They finally traced out a ground wire connector up under the dash that the factory never trimmed back the insulation - crimped it right down on the plastic. So the 12 V would show but grounded loosely back through the positive line. Under load with a bulb, it just shorted, blew fuses and didn't work. It's a real fresh assuring feeling when the dealer actually believes it's customers the first time they present a problem. As if my engineering degree wasn't a bit more education than anyone I talked to at the dealership. Yes I am talking about you Fremont Ford in Ca!
I tried 3 different 4 wire adapters for my 92 Explorer and one of those was done by a proffesional and each time I would hook up my 4 wire trailer to my Explorer the trailer lights would not work. I used a volt meter and a 4wire tester made for trailer wiring and both test showed nothing wrong. I was getting 12 volts to pigtail and was about to give up when I found out that my explorer had a towing package on it. Advance Auto had the correct adapter. The adapter was round on the end that plugs into the wiring harness on the Explorer and the other end was a plain flat 4 wire end. If this doesn't help you then there might be a trailer relay on yours. Mine was located in the back cargo area on the driverside where you fill the rear washer fluid. Yours might be in a different location.
I have seen a plug with LED lights on it that is designed to test the voltages towards the test vehicle at Auto Zone. It would be handy for isolatiing trouble between the trailer and the vehicle.
How do you know you're getting no power? A very common problem with trailers is grounding of the lights. Many installations will ground through the trailer frame, and the connections will go bad over time, sometimes over a very short time. Also as Jharger said, if you know that the trailer is OK, check your ground on the plug. Simplest way is to get a long piece of wire and run it from the - side of the battery to the rear as a temporary ground. Oh, one other thing to be sure and check is the condition of the connectors for the bulbs in the trailer. Another common problem is that the connections corrode on either the bulb or the connector (many trailer light fixtures are fairly cheaply constructed).
Seems to be a misprint in my 97 EVTM. The wiring diagram shows under hood/ power distribution box maxi fuse 8. But the list of fuses shows maxi fuse 7 is wired to the "trailer tow relays."
That's what I suspected. Make sure you check the trailer out very well. Make absolutely certain you've checked the ground connection on the trailer at both ends and in the middle. A bad trailer ground is the most common cause for a no light problem. Especially if it's no brake lights and no tail lights. Those are 2 different circuits.
Back to 86 Bronco's comment - yes if the truck has a tow package, the 97 is probably like my 93 in that a special pigtail is required. Under my truck on the dirver's side rear is a round connector that the special factory pigtail connects to. Inside this pigtail is a return wire, a loop is all, that runs from on pin on the connector to another. Therefore, when the pigtail is installed, one line is grounded out and the trailer relay pack is now energized. My initial post I assumed this pigtail was being used. If not, this might be the simple solution.