So through the grapevine I was lucky enough to borrow a trailer for a week so I don't have to rent one for our trip to the dunes this upcoming weekend... It's a long story but the lady that's letting me borrow it recently lost her husband and it was his trailer so she said make use of it because now it just sits... It's a tandem axle with brakes on one axle (I'll get pics of the trailer tomorrow)... Anyways, my truck is wired with the RV style 7 blade plug... the trailer has the small diameter circle (like 6 plug)... so I got an adapter before we went to pick it up. We hooked it all up and checked the lights... everything was working fine so we hopped in and took off... I drove slowly (we were in the dirt on a narrow road) and right away it felt wrong... dad hopped out and I rolled forward and sure enough the rear tires were locked up solid... We messed around with stuff for a minute and finally decided to unplug the harness to see if it made a difference... sure enough as soon as you unplug it you hear a *click* and the brakes let go. Sooooo any ideas? I noticed it's setup for a break-away box but there isn't a battery (the terminals just lay there)... Is it as simple as that? If it's wired for a break-away box and you don't have a battery does it lock it up? But like I said it locks up when you plug the harness into the truck and unlocks when you unplug it... Phew that was long winded... lmk if you need more info or symptoms... Pics to follow...
Just thought of a useful piece of information... I'm running a Prodigy P3 brake controller and it doesn't recognize that a trailer is hooked up...
I think that there are two adapters that are available for the trailer plug you are refering to . I had a similar problem a few years ago and it was due to the wrong adapter. LT.
The problem is your adapter. There are two different ways the 6-round plugs are set up (im assuming thats what you have). The difference is in the placement of the brake and aux power wires. Some adapters include instructions on how to switch it over but all thats involved is switching the blue and black wires inside the adapter. I actually carry one set up each way just in case. Hope this helps.
THANKS! I literally just finished up a big front end rebuild on my k10 so now 100% of my efforts are going into the trailer... Tomorrow night I'll switch the blue and black wires in the adapter and see if that fixes it.
That was it! I switched the blue and black wires and it worked like a charm... I manually applied full brake then put the truck in drive and the trailer held the truck still (this might be normal but I'm a noob to trailers)... I was surprised they were that strong... I took it for a test drive and it works perfect... the P3 controller is smooth. When I braked normally the voltage was right on par and slowed the trailer down with the truck (I never felt any jarring like I did on my last trailer that had surge brakes) and I found an open road that I could get into it a little then I got on the brakes pretty hard and it stopped straight as an arrow, again, without any jarring... So I think I'm all set... just for kicks here's some pics...
I believe its required by the DOT for the trailer brakes to be able to hold the truck still. At least, I think thats the rules here. Good to hear you got it all working.
Just got back from the trip... Everything went smooth except we had a blow-out on the way there... it's a long story but we eventually made it there and the next day I went ahead and put 4 brand new tires on it (which performed beautifully on the trip home)... The only thing that I'd change is more power in the tow rig... on Cuesta Grade I was in first gear @ 3,300rpm for a good mile or so... to it's credit though the cooling system on these old big block chevy's works great... never got above 220*... A couple pics...
