Trailer Wiring Harness Recommendation for a 1999 Toyota 4Runner

Question:

After reviewing the descriptions for these two units, it would appear to me that either would provide the output I need for my particular situation. I have a 1999 Toyota 4Runner 3-wire system which is not providing appropriate output to the existing flat 4-wire plug. I also have a 4-to-5 wire adapter installed for backup signal. Im missing brake / turn signal output. Im assuming my 4Runner brake / turn signal combining module is not functioning correctly. While both of the units above would appear to solve this missing signal problem, it appears the main difference in the two is that the Modulite system would provide power directly from my vehicle battery rather than taking power from the tow vehicle lights. Is this a necessary or significantly beneficial feature that would justify the additional expense of the Modulite system? BTW - it turns out that I do not need the backup signal for the trailer surge brake lockout on this particular trailer. Thus the 4-wire output of the C56175 unit would meet my current needs. If I later need that 5th wire, Ill still have my existing 4-to-5 wire adapter.

asked by: Dave R

Expert Reply:

If I were you I would go with the Curt Custom Fit Vehicle Wiring # C55341. This isnt one of the wiring harnesses you referenced but I believe it would be your best choice because of how easy it would be to install and because it would be exactly what you need to provide you with a functioning 4-way at the rear of your 1999 Toyota 4Runner.

The Curt Circuit Protected Converter # C56175 that you referenced is also a viable option but it would require you to cut and splice into the trailer wiring of your vehicle for it to install, whereas the # C55341 is basically the same thing except it is a plug and play model that would not require cutting or splicing.

Some vehicles require the use of a dedicated power wire to run to the battery of the tow vehicle. It is a nice feature, but since it has been determined that your vehicle does not necessarily need this protection I would not recommend you get a harness like the Modulite Power Converter # 119177KIT.

And if you already have a 4 to 5 way adapter I think just a 4-way would be fine for you.