2012 Tacoma Trailer Wiring Harness Price Puzzle

Okay, here's a good puzzle - I've got a `12 Taco that I want to put a trailer wiring harness in. The plug-in aftermarket units with converters etc. are typically in the < $50 range and the Toyota full vehicle harness for everything up to 2011 is ~$100, but the 2012 part jumps to the $150 range. Yikes! What's going on?

 

For future searchers, here's the route I went with my 2012 regular cab.

The dealer quoted me $170.00 for the OEM harness. The parts manager at my dealership is awesome. She said "go get an aftermarket one from O'Reilly". I picked up a Hopkins brand model 43355 harness for 2005-2012 Tacomas and some T100 trucks. As of 9/1/13, it was $64.00. It took all of 30 minutes to install and required ZERO splicing (meaning, it would only take 30 minutes to remove). It even came with electrical connection grease. You will need several large zip ties to hide the wires and secure the small "box" of this item to the top of the receiver hitch cross member.

Of course, I do not have any long-term reliability to comment on but it works just fine and saved me a chunk of change.

Hopkins 43355

 

Ok, there is not much on this forum I can contribute with so much, but this is one area where I am a complete expert, and I'll tell you why... My last truck was a 2004 4x4 Sr5 that did not come with a tow package. I snowmobile about 3k miles in the winter, and fish about 30 hours a week all year round, so I pull a trailer a LOT (I have 5 trailers). Shortly after I bought my 2004 in the fall of '03, I got a hitch installed by a local garage with a plug and play trailer light harness. They are all pretty much the same, they all have a converter box that gets grounded and the harness is wired in line with the taillight connectors. I just recently sold that truck, so I had it for 10 years, and over that 10 years I probably went through 8 of those plug and play harnesses at roughly $50 a pop. They all fail, and the reason they fail is because there is only one ground wire for all the circuits. With your tail lights, you have three circuits essentially- brake, turn and running, and you can multiply that by 2 for each side. In a factory harness, all of these circuits have their own individual grounds, but with the plug and play harness, all of the circuits are grounded to the truck with one, single ground wire through the converter box. So in a nutshell, all the voltage for all the circuits goes through that one, single ground wire, and therein lies the problem. Every time one of my plug and play harnesses failed, it was very easy to see where the trouble was- the ground wire was fried black.

Now, it wasn't until recently that I actually found someone who knew what they were talking about to explain why these things kept failing on me. And I didn't know until recently that you can also buy just the converter box alone, which is really all you need to replace when yours fails. They can be found for roughly $10-14. But fair warning, it isn't much fun at 9pm the night before a vacation when you have a hundred things to do and you hook up your camper and there are no lights. On my new truck I happily paid the $600 for the factory tow package. Very happily. Sorry if I gave you more info than you needed, just want to share what I learned.

 

Jethro, I have read elsewhere where others mention that the OEM harness is a completely independent circuit. If/when this aftermarket unit fails, I will buy the factory harness.

 

That's the best answer I've ever seen - thanks for passing it along! I wonder if the move to LED (low current) lights will make this better.

 

The two trailers I tow the most often have LED lights, so I don't think so, but maybe?