Trailer light/suburban

Hey all-new to me 2007 suburban trying to hook boat up for first time- getting no juice to trailer- any ideas? Am I missing a strange simple button to allow, or do I have a situation?

There is a raised pc. of plastic on the 7 to 4 connector. Make sure it is
plugged in all the way.

look at the under hood power distribution box,there,you will find individual fuses for the trailer park,and turn/brake lite fuses.
left and right hand signal fuses are individual.
if they are all blown,someone had a short in their trailer before you got the truck.
if only one,or none are blown,and you know for fact your trailer is okay,you may want to check the factory plug in adapter on the left hand frame rail near the bumper bracket,it may be either corroded,or partially disconnected,or worse yet,someone hacked the wiring job.

start with a good test light at each blade of the connector adapter and work your way back from their,but as stated,check all of the fuses first.

Check the plug in behind the bumper. The vehicle plug in is also plugged into the vehicle wiring behind the bumper. If your tail lights work you should have power to the T.

I had issues with my trailer running lights not working with my 06 trailblazer this summer. All the connections at the rear were good and the fuse box under the hood was good. Turns out I have another fuse box for the trailer lights underneath my 2nd row of seating and that fuse was blown. So if you’re second row seats flip up, see if you have another fuse box under there. As iowaboy said, there is a fuse for everything.

@p4 walleye – no lights at all to any of the circuits? Does this trailer work on a different vehicle?

The last three years have been a personal fiasco for trailer lights. I tow multiple boats during a year but it’s my buddy’s that we use for Canada as the consistent trailer. Vehicles are somewhat similar, 2002 Yukon XL(this year), 2014 Silverado(earlier this year), and a 2004’ish Trailblazer(last year).

All thoughts below are based on your trailer working with a different vehicle.

x2 – check the pin adapter. Even if plugged in properly these things go bad.

Basic rules of trailer lights. It’s the ground. Rule #2, refer back to rule #1. 90% or greater of light issues are due to the ground.

With an 8 year old MN vehicle I’m guessing the metal is not a rust free and perfect as it once was. Connect a wire from one of the bolts on the trailer then run it underneath to your vehicle frame. Make sure where you attached it is rust free or make it rust free.

For me at least the other 10% are fuses. I don’t think this is your issue. The fuses are typically for one part of the lights or another. When this is bad for me an example is losing running lights but brakes still work. That said, this is an easy thing to check. I’ll bet your trailer fuses are under the hood based on what I’ve seen in full size Chevy’s. Either way, your manual will have this.

Best of luck and let us know what it turned out to be. I might need the advice in a parking lot up north next summer. Spent the night in the truck in Virginia in June and International Falls in September Would like to start avoiding that.

When you say, “no juice”, have you checked the suburban plug with a test light or meter? That will let you know which direction to go for diagnosing the problem.

If you have the factory 6 prong plug, pull the harness out of the backside of that plug. I was having light issues on my 2001 Suburban and could not figure it out. One day I found out that there is a plug that plugs into the 7 prong adapter, just under the bumper. I looked in there and a number of the metal connectors were very corroded. I cleaned them all up with some sandpaper on the end of a screwdriver, plugged it back into the back of the 7 prong and now my lights work great!

311hemi wrote:

If you have the factory 6 prong plug, pull the harness out of the backside of that plug. I was having light issues on my 2001 Suburban and could not figure it out. One day I found out that there is a plug that plugs into the 7 prong adapter, just under the bumper. I looked in there and a number of the metal connectors were very corroded. I cleaned them all up with some sandpaper on the end of a screwdriver, plugged it back into the back of the 7 prong and now my lights work great!

Do you guys in the Midwest hit all your electrical connections with no-ox grease to prevent salt corrosion?

Thanks boys! I will report what I find!