Trailor lights

[cryoman]

Need help guys , rewired truck trailor connection , no lights on trailor , I think i shorted something out . All fuses under dash okay , Mayby change relay I have a 94f150 any suggestions

 

[EZLoader]

Re: Trailor lights

Check that your wires and leads aren't corroded anywhere and that you have a good ground.

 

[Pony]

Re: Trailor lights

do as EZ says.... DC hates corrosion.

 

[Silvertip]

Re: Trailor lights

You need a couple of things to diagnose the problem -- a battery charger and a volt meter or test light. If you have a battery charger, connect the ground lead to the trailer frame. Put a nail in the positive lead and touch each of the pins but don't do the ground (white) pin. The brown wire should light both tail lights. The other two wires work the left and right turn signals (they will obviously not blink but will be on constantly). If the lights work, the problem is either that you have a bad ground on the trailer or you have a mismatch or bad wiring on the truck. I must assume you did the obvious and checked the bulbs.<br /><br />Use a voltmeter or test light to make sure the connector on the truck has voltage at it when the turn signals and lights are on. If not, its fuses, wiring, or bad ground. Get the trailer working first using a battery charger. then go after the truck.

 

[EZLoader]

Re: Trailor lights

UpInSmoke...that is great advice. I like that that approach. I'm going to remember it. Thanks!

 

[Bondo]

Re: Trailor lights

I'm Not Sure,........<br /><br />But,....... I Think that you'll find a Fuse Box under the hood of the 94 Ford pickups that have the Trailer Circuit Fuses........

 

[rwidman]

Re: Trailor lights

If it was working before you rewired it, that's where I would start. You either wired something wrong or you blew a fuse by shorting something out while you were working.<br /><br />Upinsmoke posted a good way to troubleshoot the trailer but if you didn't work on the trailer wiring the problem would not be there.<br /><br />Auto parts, trailer, and marine retailers sell a test light that plugs into the tow vehicle connector and lets you easily check to see if there is a problem with the tow vehicle wiring.

 

[Dave Abrahamson]

Re: Trailor lights

All my lights worked except the running lights. It was a 10 amp fuse in the power dist.box under the hood. '03 Dodge but I believe ford has one under there also.

 

[gonefishie]

Re: Trailor lights

Great idea upinsmoke! would a battery work as well to do the testing? battery charger puts out lot of current, I thought it might blow the bulbs.

 

[Silvertip]

Re: Trailor lights

A battery works ok too. As for current output, a battery can be used as a make-shift welder and has hundreds of times more current capacity than a charger. Besides, the battery charger will only put out the amount of current a circuit draws from it. In otherwords, a light bulb draws less than one amp whether its from the charger or a battery. A starter can draw hundreds of amps from a battery (it all depends on the size of the starter of course). Its the load that determines how much current is drawn from a source -- not that the source simply dumps everything it can into the circuit.