trailor light trouble

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Mar 28, 2015 | 03:05 PM

#16

Ford89mustang

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Quote:

Originally Posted by ligito

If you have the auxiliary battery, check the state of charge and the connections.

I have the duels since its diesel and both are in great condition, brand new cable between them down to the starter.

I tried reading the voltage across fuse 6 and not getting anything. Not sure why that is.

Mar 28, 2015 | 03:21 PM

#17

ligito

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From: Oregon

A connection on one of them may be causing your issue.

Mar 28, 2015 | 04:51 PM

#18

Ford89mustang

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These are the underwood relays. No idea which group does what.

Mar 28, 2015 | 04:52 PM

#19

Ford89mustang

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The other wires are some custom wiring. I have slip tank pumps and exterior lighting etc, don't have factory up fitter switches so did all my own relays.

Apr 8, 2015 | 09:01 PM

#20

Pipewrenchf350

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I don't mean to hijack this thread. But my 2002 f350 psd has no trailer running lights but every thing else is getting power. The fuse number 38 is good. I hear that there is a running light relay that is embedded relay in the single fuse block under the dash. Is this true ?

Apr 9, 2015 | 08:51 AM

#21

speakerfritz

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use a 7 way plug with LED's to verify your connector.

I troubleshooted a trailer weekend that just passed with the same problem....issues was grounds at each of the trailer lights. ran a star ground from each of the lights mounting bracket to the trailer connector ground and everythig worked fine.

other option would have been to weld the trailer mount brackets to the frame.