Troubleshooting 4-way Wiring on a 2001 Ford F-150 and 6-way Wiring on a 1989 Jayco J Series Trailer
Updated 07/26/2013 | Published 07/25/2013 >
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Question:
I tried to get help from another experts and it cost me 49.00 earlier today. and I got no where.He said he could not help me. He said I need to ask a jay co expert. the trailer has a 6 square pole and the truck has 4 way flat. inside of my truck has a break system pro logic. Now the truck turning signal works fine.but when I turn my left blinker - All of the lights on the trailer blinks. now when I turn the right blinker - no lights. and when I apply the breaks they work - all lights work. I need to get this working by tomorrow. I am leaving town for family reunion, Can you help?
asked by: Sandra
Expert Reply:
I would suggest checking all the fuses on your vehicle and make sure they are in proper working order. Then using a circuit tester like part # PTW2993 to test the signal at the truck 4-way and make sure that the trailer is getting the proper signal when the functions are activated.
If you are not getting the proper signal from the 4-way a replacement kit for your truck would be Curt # C55256. This wiring harness is a T-one style that plugs directly into your OEM wiring harness. If your truck does not have an existing OEM wiring harness, then you can use the # 18252 and splice into your trucks existing wiring to establish a new 4-way connection.
If your 4-way is working properly on your truck then you will need to use the Mighty Cord adapter 4-way to 6-round, then the Hopkins adapter 6-pole round to 6 pole Square # HM7415 to connect to your Jayco Pop-Up Camper.
Since you are using a 4-way flat supplying the signal to your trailer on that wiring harness the brake light and signal is combined using the adapter mentioned above the signals should work properly and will be configured properly for your trailer side 6-way plug. If you or the previous owner has not disturbed the wiring on the trailer, then using this adapter should solve your problems.
If you are still experiencing the lighting issue after using the connection adapter, then you would need to troubleshoot the issue. You will need to test the functions on the trailer side connector and make sure that the functions match the function configuration of the adapter plug. The adapter plug is configured according to the attached diagram.
You can check the configuration of the trailer connector by either tracing the wires from the connection point to the corresponding function on the camper, or by electrically testing the function connection points. To electrically test the connection points, you would start by connecting a jumper wire, that is insulated except at the points of contact on the battery terminal and the trailer connection point, to the positive side of a 12V Battery and activate one of the connection points on the trailer plug at a time to determine the function of that connection point. If the trailer plug is not configured the same as the adapter plug, then the functions will not work properly, and the plug will have to be re-wired.
If the truck 4-way, and the trailer connection configuration checks out then proceed to troubleshooting the trailer. The first thing that I would check would be to make sure that the trailer has a proper ground. If the ground is connected then start by tracing the wiring and inspecting for any signs of corrosion, damage to the insulation, or exposed wire. Pay close attention to area near moving parts like the suspension.
I have provided links to the parts listed above, and installation video, and links to a couple of helpful articles that helps walk you through several troubleshooting processes.
Product Page this Question was Asked From
6-Pole Square Trailer Wiring Connector Kit (Car and Trailer Ends)
- Custom Fit Vehicle Wiring
- Wiring Extensions
- Universal Fit
- 6 Square
- Plug and Lead
- Hopkins
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