Question:
My friend has a cargo trailer with brake/turns lights and a 7-way blade conector. The lights work correctly on my 1999 Dodge 2500 and my friends 2007 GMC 2500, but not on his older Landcruiser that has separate turn/brake lights with 7-way connector harness. Do I need to rewire the Landcruiser with a newer harness or is there an adapter? Like the P-119130
asked by: Paul
Expert Reply:
Since the trailer lights work fine when being towed by other vehicles, the problem is clearly with the vehicle. I would recommend you use a Circuit Tester, item # 40376, to test the trailer connector on the Land Cruiser. Test the lighting pins on the connector as each lighting function is activated.
Do you know if the trailer connector on the Land Cruiser is factory or aftermarket? If it is factory installed, there should be fuses on the vehicle that manage the towing circuits. One of these fuses could be blown. The vehicle owners manual should offer more information regarding the specific location of these fuses.
If the connector is aftermarket, there should be a taillight converter, like the small box you see on the part # 118130 that you mentioned. Find this box by tracing the wiring back from the trailer connector, and use the circuit tester to test the wires entering and exiting the converter box.
If there is a signal going in, but not out, the converter has gone bad and must be replaced. If you need to replace the converter, the part number 119130 that you mentioned would work fine. If the 7-Way connector is more than several years old, and is showing some corrosion on it, it might be a good idea to replace it as well.
We offer a 4 to 7-way adapter, part # 37185, that the converter would plug right into, requiring no cutting or splicing. We have a video that outlines the complete procedure for troubleshooting your trailer connector, I will include a link to the video which can be found below.
expert reply by: Mike L

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Products Referenced in This Question
Adapter 4 Pole to 7 Pole and 4 Pole
Product Summary:
Wiring Adapters
Single Function Adapter
Product Specs:
Plug and Lead
4 Flat
7 Blade
4 Flat
Product Page this Question was Asked From
Upgraded Taillight Converter by Tow Ready with 4 Pole End
Product Summary:
Trailer Hitch Wiring
Converter
3 Wire System
Universal Fit
Product Specs:
4 Flat
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