Factory Trailer Connector on 2006 Toyota Tundra Has Running Lamp and 12-V Circuits Reversed

Published 02/27/2021

Question:

I just installed the H20046 RV cable 7 way, replacing my trailers existing 4 wire so I could plug into my 7 blade on the 2006 Tundra. I got everything sorted except the 12V battery power. On this plug I am getting that 12V power on the thin brown wire instead of the big 10 gauge black wire like Im supposed to. Ive checked the female plug on the truck and it appears that the 12V battery is in the wrong spot, but its all factory and stock and its never been messed with. What do you think my options are? Rewire the truck plug?

asked by: Rick

Expert Reply:

We see this every now and then with Toyota and Nissan trucks for some reason. It sounds like your running lamp circuit and the 12-v feed are reversed.

The easiest thing to do is just rewire the connector on the truck, so your connector will be correct in case you ever need to tow anything else.

I'll link to our trailer wiring help article, which will show which terminal on the back of the truck's 7-way serves which purpose.

expert reply by: Mike L