Trailer lights

[golver]

My trailer lights are one of those after market kits with the two full light attachments and the wiring harness with 4 prong plug. I use a converter to change the 4 prong square to a 7 round to fit my truck. The problem was occuring before I got the adaptor.<br /><br />Both blinkers and hazards work all the time.<br />Brakes work when the headlights are off.<br />Tail lights work when the headlights are on.<br />If I hit the brakes when the headlights are on, all lights on the trailer go off.<br /><br />Besides that, they work perfectly. Any idea why this happens? I am assuming in correct wiring, but can't figure out what I did wrong? Bad bulbs?

 

[Bob_VT]

Re: Trailer lights

You have to research you 7 round at the truck end. It sounds like it is either grounding out or loosing ground. <br /><br />You might want to get the proper plug for the truck and slice away the adapter after you figure out the wires.<br /><br />WIRING<br /><br />4 way plug through 7 way plugs all have the basic same color patterns.<br /><br />GREEN Right turn and brakes<br /><br />YELLOW Left turn and brakes<br /><br />BROWN Marker lights/running lights<br /><br />WHITE Ground<br /><br />RED Auxilliary power (winches ect)<br /><br />BLUE Electric brakes<br /><br />Purple Back up lights<br /><br />If your vehicle has Europeon Standard turn signals (AMBER) then you can purchase a converter at an auto parts store to accomodate the wiring change. Standard T connectors are now sold for must vehicles which is like "plug and play".<br /><br />Just verify the truck is right.<br /><br />Bob

 

[bubbakat]

Re: Trailer lights

this might help a little diag of sevenway plug male and female

 

[roscoe]

Re: Trailer lights

I bet its a grounding issue.

 

[Silvertip]

Re: Trailer lights

Using a battery charger, connect the negative lead to the trailer frame. Put a nail in the positive lead and then probe the brown wire. The side marker lights and tail lights (dim) should come on. Then probe the yellow and green wires. The right and left turn signals should come on (bright). Now disconnect the negative battery charge clip and connect it to the white wire pin and repeat the tests. If everything worked fine in the first tests but not now, you have a ground problem. If they didn't work properly in the first test, you need to fix the wiring. Also check that the dual filament bulbs are not only good, but that they are properly inserted in the sockets. They are keyed to go in only one way but the sockets are so cheaply made bulbs can be forced in 180 degrees from where they should be which can cause problems similar to what you are experiencing.

 

[Bondo]

Re: Trailer lights

Originally posted by roscoe:<br /> I bet its a grounding issue.

No Doubt About It,.............<br /><br />Hook a set of Jumper Cables to the Trailer Frame,+ to the Truck Frame,.............For Testing purposes......<br /><br />Your Troubles will Disappear............

 

[golver]

Re: Trailer lights

I will check the bulbs and try the gound. <br /><br />It has nothing to do with the 4 - 7 convertor, as it was doing this when i used a 4-4 connection also.<br /><br />Thanks for all the help.