Reverse lights and Trailer wiring

I posted on this a while back, but the issue was never resolved. However, the "symptoms" have improved.

When I hook up the trailer wiring to the rest of the truck, when I press the brake, the reverse lights come on just like the brake lights do. No other symptoms. Fuses are all fine, I'm guessing that the reverse light wire and the brake wires are touching or somehow in the wrong place? I am not electrically inclined, so sorry if this is an easy fix and I just missed the solution. I'm moving in 3 days and will be hauling a rental trailer so I have to have this working by the time I get the trailer. I'm going to look for wiring diagrams in the meantime. Thanks for all you do!

EDIT: Found this, just have to make sense of it now.
http://www.customtacos.com/tech.old...toyewd/06toypdf/ewd/2006/tacoma/h/em01d40.pdf

 

When you say reverse lights come on, on the vehicle or the trailer?
On the vehicle the reverse lamps are a bulb and circuit apart.
The tail and stop lamp on the truck is a 2 filament bulb, and the turn is a one filament alone/separate circuit bulb.
Does the truck have the 4 pin or the 7 pin towing connector?

 

Do you have a 4 pin or 7 pin connector? Is it factory or aftermarket trailer wiring? Look for signs of corrosion on or in the connector, electricity can flow from one circuit to another due to the corrosion. Usually this is the most common problem. If it’s aftermarket wiring maybe they used a converter and it failed. Most aren’t waterproof and fail after sometime. When they burn out they can short and send power from one circuit to another. If you can provide more info, we could be of better help

 

Does the trailer have a 4-pin or 7-pin wiring harness? Sounds like the trailer wiring might be funky, and the brake wire (blue) is energizing pin 7 (purple) on the truck connector.

https://www.etrailer.com/faq-wiring.aspx

 

I have a factory 7 pin, the trailer will use an adapter for 4 pin. I took out the reverse light bulbs and just gonna call it good for now I think. As long as the lights work on the trailer (which they did on my neighbors) I'll be ok.

 

The reverse lights on the truck. 7 pin.

 

Look for corrosion in the connector or the backside of it

 

Cleaned out the connections, they look alright.