Suggestions on electrical gremlin??

[SHobbs]

Hooked up the 5'er to head to OK this past weekend and the lights were acting weird. About two minutes after I plugged in the 7 way plug my brake lights came on, the truck and the trailer. My right hand turn signal would work but, the left signal gave me an indication then a slight buzzing noise with no blinking noise or blinking. Unplug the 7way plug and all is fine as far as the truck goes. I am leaning towards either replacing the 7 way plug or the emergency brake away cord. All worked fine the first time I plugged the trailer cord in until I hit the brake pedal then the brake lights stayed on all the time. I hate these kinds of problems being that they are difficult to track down, any help is appreciated. Thanks guys.



Scott

 

[Bloomy]

Scott,



I will second your thoughts on replacing the 7-way connections. After dealing with problems that were similar, I replace the truck side and trailer side once a year. Since living in the north, the salt from the winters would corrode and short out. Check the truck side with a multi-meter to make sure each terminal is getting power only when it is suppose to and go from there.



Thomas

 

[p-Bar]

Scott,



I will second your thoughts on replacing the 7-way connections. After dealing with problems that were similar, I replace the truck side and trailer side once a year. Since living in the north, the salt from the winters would corrode and short out. Check the truck side with a multi-meter to make sure each terminal is getting power only when it is suppose to and go from there.



Thomas

And also get a 12volt battery and send power to the trailer and make sure all is fine on that end also

 

[jelag]

The brake away switch has nothing to do with the areas your talking about so I wouldn't worry about it... . I'd pull back the cover on the male plug that's attached to your trailer and check those connections and see if there is some action between the wire and terminal..... if so clean the connectors or replace it... . and put some dieletric grease on the connections before you put it back together... ... the next step I'd take would be to check the grounds on specific circuits to make sure they are making a good ground to the frame of the trailer and than the ground wire from the frame to the connector...



Hope this helps.

 

[TurboCanScoot]

Gremlins

Scott,



The replys you have gotton are steering you in the right direction. Your 3 main points of failure are the 7way termination, where the wire terminates on the harness, the wire. I have worked with testing 48 to 260V DC circuts for the last 7 years. The best advice I have for you is to start at the furtest point out and work your way back to the harness. Make sure you have a good Meter with good cords. That will solve a lot of your frustrations. I have a fluke with the regular test probes and a set of cords that have alligator clips with "Bed of Nails". If you use the bed of nails make sure you seal up where you puntured the plastic sheath. Also get under there and check to see if anything is rubbing the harness. You could have something going to ground or shorting that shouldn't be.



Like the guys are saying check the 7way and make sure you find the correct signal where you are supposed to. When ever I get a trouble with more than two wires a picture is priceless.



I just found this diagram for the wiring harness. This should help simplify things: Trailer Wiring Diagram For 4 way, 6 way and 7 way circuits



Regards,



Richard

 

[SHobbs]

Thanks for the replies guys. The reason I was thinking about replacing the 7way plug was that I accidentaly left it plugged up when I pulled away from the 5'er once. As far as the battery goes it is dead. Something else I did not mention was the fact that when I used a pipe cleaner to clean out the male end of the plug ( trailer end ) one of the terminals was hot, by that I mean that there was a little smoke that came out of the plug. I have replaced both tail light bulbs on the 5'er thinking that there might be some corrosion there which did not solve the problem. Oh by the way I did try the 7 way plug down by the receiver hitch to see if it did the same thing and it did, so it looks like it's on the traier end, hopefully.

Richard thanks for the diagram that is a big help.

Scott