Brakes lock up when backing

[Hellsranger]

I need to be advised. I just bought a 91 CD22 Cruiser on a 91 King dual axle trailer. My truck has a 4 wire flat plug, the trailer has a 5 wire flat plug, I plugged it in and all the lights worked so off I went. When I got to where I'm keeping the boat for the winter, I attemped to back the trailer into a spot and the trailer brakes locked up. It's a gravel lot, so I put the truck in 4 low and skidded it into the slot. Will rewiring my truck with a 5 wire flat plug solve this problem?

[Brewkid]

You likely have hydraulic surge brakes. If your backup solenoid is not wired correctly or not working, that will happen.

John
Scallywag

[Wandering Sagebrush]

[Hellsranger]

Thanks John
I appreciate your input
I'm new to this and this forum is gonna be a life $aver

Thanks Wandering Sage Brush, nope, no manual

Mac

[Ferg]

It looks like the hydraulic solenoid over-ride is not engaging. I’ve been through this before. Just because you have lights, it doesn’t necessarily mean that the backup connection is making contact.

Here’s what worked for me - thoroughly clean the male and female plugs and spray with WD40. Apply a small of dielectric grease on the connections.Don’t use too much grease, because it’s really an insulator, not a conductor.

[hardee]

Here's my bet. You have surge brakes on the trailer. One wire from your truck should be hot when you put the truck into reverse. (That is when your backup lights come on on the truck.) That wire should activate your surge brake lock out to keep it from applying the brake as the truck to tongue pressure increases (which is what happens when you are towing forward and apply the brakes in the truck). There should also be a way to manually lock out that surge brake (a key or bolt to keep the hitch from compressing in the trailer tongue, activating the surge hydraulics, and allowing you to back up.

Look at your trailer tongue, close to the hitch for an elongated hole, (oval ends are fore and aft with the trailer), or a hole or slot to put a pin, bolt or lock through that prevents a ram from the brake cylinder to move fore and aft.

Also find a wiring diagram for the truck and see if it matches the trailer and also see which truck wire is not being connected to the trailer.

Sure hope that helps, and congrats on the new to you 19.

Enjoy,

Harvey
SleepyC

[rbfconstruction]

I had the exact same issue. It was the solenoid that needed replacement. They have a 4 to 5 adapter at the auto parts store. My trailer had two flat hook metal arms behind the ball socket (sliding out of the trailer towards the truck). Yes, I put a bolt in there to bypass the brakes, so I could get it to the trailer shop.


Richard

[localboy]

Been there. Done that. Back up solenoid needed replacement. Not difficult, but you will need to bleed the entire brake system after it's installed. To test apply twelve volt power hot/ground; you should hear it "click".

[thataway]

A four pole plug will have trailer running lights, right turn, left turn, and brakes (Rt and Lt turns combined).

A 5 pole plug will have the above, plus the blue wire--which is the reverse lock out for the solenoid.

At this post, since he has never energized the 5th pole *(the 5th on the input), we have no idea if the solenoid is good nor not.

It the truck has the 7 pin standard tow plug, then you get a 5 pin adaptor, and that should energize the reverse lock out solenoid.

If the truck is not wired properly--(and some are wired for electric brakes), then the blue wire or 5th pole goes to the reverse light. Problems solved.

There are many ways to mechanically lock out the brakes (only in reverse!), and those include a pin or bolt thru a hole. Many trailers do not have that hole--and you can put a large C clamp over the frame, or I carry "Chain Vise Grips" which are handy for all sorts of things, and use those.

[Dan McNally]

Bob is correct again his description is spot on.
Dan

[nordicstallion]

I switched from drums to kodiac disc brakes & new surge brake. First thing I noticed was the trailer wheels locking up in reverse. I've read that the reverse solinoid lockout fails regularly. I just drilled a hole thru the surge brake & put in a lockout pin when I back up, problem solved..forever!

[Marco Flamingo]

Mine has a little hole for a lockout pin. When needed, I pull the lock pin on the hitch handle and use that if I need to back up and the electrical isn't working properly. The pin is connected to the frame with a stainless braid wire, so it's always there when needed.

Find the manual for your receiver on line. You will need to know how and when to bleed, replace fluid, etc.

Mark

[tsturm]

[PaulNBriannaLynn]

I had a 2003 King double axle for years, and it would do exactly what you describe.

I had a bolt that I would put in the coupler to lock out the brakes when maneuvering around parking lots or backing up, and when I was on the highway I would take the bolt out.

Unfortunately I never knew there was a solution so I just dealt with it, and sold that boat before ever fixing that issue.

[olsurfdog]

My '07 E-Z Loader trailer does not have a solenoid either. There is a button on top of the coupler/ brake applicator. This must be turned to lock out the brakes for backing. Then, don't forget, after backing, to turn button back before driving off (or brakes won't be working!!).