Trailer brakes engaging when reversing - troubleshooting advice

RobTX

Cadet
Joined
Nov 4, 2013
Messages
25
Hello all,

Took my new to me boat out for the first time and when putting into my storage area, which is on a slight uphill grade, I noticed my trailer brakes engaging. I have a four pin connector on my truck, which I recently installed a four to five pin adapter, with a blue wire to energize the reverse solenoid. I spliced this blue wire to the hot lead on my reverse lights. In terms of troubleshooting, I was going to go through this as follows:

1) Ensure the blue wire is carrying voltage - determine how much
2) Ensure the reverse solenoid is actually receiving that voltage
3) Ensure the reverse solenoid is actually working

These seem like logical steps, but, as a new trailer owner, not sure how to do any of this (or if I'm missing something). Any advice on which voltmeter to pick up, how to identify the reverse solenoid, or troubleshoot would be helpful.

As of now, I'm in a tight spot, as backing the boat into my storage space is a challenge- if there's some quick and dirty way to bypass the brakes in reverse that would also be helpful while I try and get this working correctly.

Thanks,

Rob
 

toms26t

Cadet
Joined
May 29, 2012
Messages
20
Depending if you have electric or hydraulic, If you have surge brakes, some of the hitches have a hole available to insert a pin while backing in your situation. You might check your setup with the trailer unhitched.
 

four winns 214

Senior Chief Petty Officer
Joined
Oct 25, 2008
Messages
757
The solenoid will be in the hydraulic line somewhere from coupler to brakes, most likely towards the front near the coupler. Until I changed couplers, mine was located at the trailer frame "Y" at the front of the trailer near the winch post. On my new coupler, it is located next to the master cylinder. My trailer also has a quick disconnect fitting in the hydraulic line to accommodate the removable tongue. That is another way I have to prevent brake pressure from being applied. If your trailer tongue has a removable tongue (most don't), it should have a quick disconnect.
 

gtochris

Senior Chief Petty Officer
Joined
Aug 4, 2010
Messages
742
Do you have a backup pin you can put into a spot on the coupler to prevent the brakes from engaging? My old trailer had one and it came in handy at times.
Other option, unplug, put the plug in so that the 5th lead (backup one) is plugged into the first lead on the car side, turn on your headlights- that way your headlights are powering the backup lead and you should be able to backup.
I had to do this once as for some reason, the reverse solenoid wasn't working as designed.
 

RobTX

Cadet
Joined
Nov 4, 2013
Messages
25
Hi all, thanks for your replies...it led me down the right path. My trailer has a sliding pin that engages the lockout. Thanks also for the rundown on how to troubleshoot the solenoid.
 
Joined
Sep 17, 2014
Messages
22
Thats not how to fix your issue, the fifth blue wire is the cut out for the brakes when you back up. You need to check and make sure your vehicle is equipped for the reverse cutout after that hook the bkue wire to the reverse pin on the 7pin connector. I do this type of work on the side and its funny how many full size trucks are not fully equipped for this, sometimes its just a five dollar relay and otheres I have to run wires to get it done correctly
 
Top