Trailer help, Can't backup
 

Towed the boat to Offshore Perf. for some spring upgrades and discovered I can't backup. Had to do the C-Clamp thing on the coupler. I sure someone on this board has had this problem before. It looks like only one wire coming from solenoid connected to brake line behind the coupler. How are these things grounded?
I already verified 12 volts on the lead to connected to the backup lights on the truck. Has anyone drilled a DICO coupler to allow a pin to be used?

The single wire from the solenoid is not a ground wire. When 12v is applied to that wire, such as from your backup lites, it energizes the solenoid and prevents the trailer brakes from working so that you can back up now. But, you must have been going forward before putting into reverse to allow the trailer hitch to extend in order to relieve any trailer braking pressure.
Also you can't back up an incline, put truck in forward to reposition and then back into reverse, won't work. You would have to block the trailer wheels and roll truck forward to extend trailer tongue 1st, then back into reverse for your final position.

Tie Down sells a very nice solenoid that will relieve all pressure in trailer that eleminates this design flaw of the standard back up solenoids.

US1 Fountain

I knew the wire coming from the solenoid was not a ground. I meant to ask if the solenoid requires a ground and/or how is grounded.

BTW thanks for the info about new solenoid type.

Its grounded just from the mounting to the master cylinder and brake lines. No ground needed.

A trick of the trade:

In a pinch if your not wired for the solenoid you can plug it into the prong for the trailer lights and turn on the vehicle lights, that blocks it too and can get you out of a tight spot sometimes.

That's how I did my last trailer. Just carried a jumper wire with aligator clips. My driveway was the only place I have ever had to back up hill, so never been a real issue. My new Eagle trailer I just order, I had it equiped with the back up option. Man was I dissappointed when it was just the cheap $30 Tie Down solenoid. Thought it would have been the upgraded version, which is only around $60 for the part itself. Or at least for the extra $300 I paid, it should have been!