OEM 7 pin Trailer Connector

I have a new 2010 2WD DC V6 TRD Sport with tow package. Last week when towing my boat, the trailer brakes wouldn't release when backing up. They worked fine with my old Tahoe (same 7 pin connector). I put a voltmeter on the center contact (back up lights) of the Taco's connector and get 0 volts when I select "reverse". My understanding is that I should get 12v power to that contact to cause my trailer brakes to release and enable me to back up. My brother also has a new Taco and he reports the same reading: zero on the center contact in "reverse" gear. Any thoughts??? I'm heading for the dealership monday morning.

 

I should have made it clear that the boat trailer has hydraulic surge brakes with an electric solenoid that releases pressure to allow backing up. Others in this forum have said the center pin of the connector has 12v when the trans is is reverse, but mine does not.

 

I'm looking at the wiring diagram for my 06 (alldata do it yourself subscription) and the only wiring connector it shows that would affect only the trailer backup light is all the way at the back of the frame where the trailer harness plugs into the main truck harness. If your 2010 is the same and your regular backup lights work, I would think you have a bad pin in the frame harness wiring plug at the back of the truck, or a bad splice. Time to visit the dealer.

 

Keep us posted on this, as I got the towing pakage too and would like to know.

 

Here's the latest:

I took my truck in this morning for a few different problems, so I dropped it off early here at Mossy Toyota in San Diego. The service manager called hours later and stated that the connector "doesn't come wired that way" and I need to use some kind of adapter to make my trailer work.

I rode my motorcycle down there to take the truck for a test drive with the mechanic for another problem and as we were driving I told him about the wiring problem. When we got back to the lot, I showed him the connector cover that states the center pin is "backup lamps". He said he'd do some research.

When I went back later to pick the truck up, the service manager changed his story: "You got a bad relay!" So, it's on order and hopefully I'll be able to back my boat trailer up soon.

 

so...............what was the fix? im having the same problem backing my boat trailer

 

The dealership replaced the bad relay and all is well. You should have 12v on the center pin of the trailer connector when the transmission's in reverse, if not, the trailer brakes won't release.

 

Do you have a part # on the relay ? I have been to 2 dealerships here and both are telling me to install a brake controller,I know thats not gonna work.

 

I traded my Tacoma in for a new Tundra last year so I don't have the service records anymore. Sorry. Tell your dealership to measure the voltage on the center pin of the connector (with transmission in reverse). If it's "0", tell them to do their research as it should be 12v and they need to fix it. If you're towing a trailer with hydraulic surge brakes, you need that pin to have 12v to be able to back up any slight incline.

 

Will do, taking it back tomorrow. Thanks for the help............

 

I have the same problem and went to my boat dealer. He laughed and said what kind of truck, a Toyota?

Apparently they have a few new Tundras in their fleet, and had the same problem. They found out that if you turn on your headlights, the problem goes away! A very simple yet strange solution. I'm going to try it out tonight for sure....