My 2011 has the factory 7 wire trailer connection. How big a load can the back up light wire handle? I would like to add a set of back up lights and tap directly into that wire but i was not sure if it could handle a set of 55 watt lights. The other option was going with LED backup lights but my local parts dealer said you might get flickering with LED's if the wire does not provide enough power. Anybody know?

 

No def don't do that. Use a Relay. A Relay will only draw ~250mA off the circuit and allow you to separately power up the lights off a fused line directly to the battery. 2-55w lights is ~9A of draw.

I tapped my reverse wire that is between the battery and firewall. I have my back up lights and rear camera tapped off of it running 2 separate relays(~500mA of draw)

 

Yeah, that's what i did on my 06'. I was hoping to avoid the cost and aggravation of running a dedicated line for something i use so little. I did so many projects to my 06' that while worth it at the time ended up being a total loss when i traded in the truck.

But what is the maximum amp draw the backup wire for the trailer harness can handle? It has to be something substantial? The White Night back up light system uses two 55 watt bulbs and the instructions tell you to tap the trailer backup wire. They even sell a harness to do it. The LED lights i am looking at from Rigid only draw 1.45 amps each. Would that really be a problem?

 

Agree with dirtydog, I looked up the circuit from the TIPM and is is not fused. I was looking for the size of the fuse to get an idea of the amperage. Basically, the signal dissapears into the TIPM "electronics" and is described as driven by some kind of circuit - probably a big FET.

 

I do not know what the rated line output is for the auxillary circuit is.30A? I can tell you that the reverse output is not going to be enough to power up your lights, Especially once you hook up a trailer... The left and right sides are only on individual 17A circuits. I imagine that you could probably get away with tapping off of the Aux line for power and use a relay for switched signal off the reverse wire(use a diode)

2006 was a bad year for blowing TIPMs on the trailer circuit because they were set at 15A each side from the factory. This required a reflash(if not blown) and a new TIPM(if already blown) Once a circuit detects over draw, it shuts it down..permanently..Expensive repair you don't want.
Take the time and do it right. These trucks are pre-programmed for every circuit and are not capable of handling more current than designed. There have been aftermarket bypass units even made but even those still require a working trailer circuit because the trucks turn signals are linked into the trailer as well.

I have mine set up so the reverse lights will only activate when the headlights are switched on AND the truck is in reverse. I did this because I didn't want or need them to turn on in the day every time I use reverse. It requires 2 relays and an additional connection on the headlight circuit. Since I have my own relay harness for my HID retro-fit, it didn't bother me as much to tap off the headlight circuit since I was using the power from my own harness. You could do the parking lights as a second trigger instead of the headlights. This way you will be able to keep all the connections out back. I would highly recommend putting the relays inside of a ziplock baggie and taping it up to keep moisture out of the connections.


I just found this......

White Night directions:
"The wiring of the White Night unit is very simple and straightforward. Each unit has 3 wires that must be wired to your vehicle to make the unit operate. The red wire needs to be connected to a 12 volt source. The yellow wire needs to be connected to the back up light wire of the vehicle. The black wire needs to connected to ground."
This does not say you must connect to the reverse wire for full output. Clearly they are using a relay and getting power from a battery source.

2nd way of wiring:
"If your vehicle has either a 6 or 7 pin trailer wiring connector you can simplify your installation (see below.) These trailer wiring connectors have a 12 volt wire that you can use as your 12 volt power source. The 7 pin connector also has a back up light wire that you can use as your back up light wire source."
This is telling you to use the Auxillary wire as power source and back up for signal source.

So both ways are using a power source and a reverse line as the switched wire and are controlled by a relay! Just as I recommended.

 

TIPM= No fun. Oh well. Maybe once the weather gets above 20 degrees ill feel more willing to start a majoring wiring job. Until then, ill just be patient. Thanks for the help though as always.

 

You can use relays, just diode isolate is all.

I can make you a harness however you want/need it if your not comfortable doing so yourself. I have all the fixings since I regularly do various types of electrical installs for local folks.