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7-Way Trailer connector

Yahoo Message Number: 68865
? I will be towing a cargo trailer this summer and have purchased a wirless electric brake controller. Did CC wire the connector with 12v power in the 7-way plug? If not, what do I need to do get 12v power back there? The brake controller requires 12v power from the motorhome to the controller. This is all new to me so please excuse any incorrect terminology.

Judy

'06 Inspire 51760

Currently at Pueblo El Mirage RV Resort
near Phoenix

Re: 7-Way Trailer connector

Reply #1 –
Yahoo Message Number: 68869
The 12 volt source you need is under the dash not in the trailer plug. You need a hot 12 volt when ignition is on, a ground wire to the control, a wire from the brake light switch to the control and a wire from the control to the back that connects to the brake wire on the trailer. The only wire to the back is the wire from the control to the trailer brakes. Should find a un-used wire from the front to the back. Mine had several un-used wires located in the wiring bundle in the back.

Leonard

97' Magna 5418

Re: 7-Way Trailer connector

Reply #2 –
Yahoo Message Number: 68871
? Leonard thanks for the reply, but I am more confused than I originally thought! My setup is a Teknosha (sp?) Prodigy wireless brake controller. Supposedly, what I'm supposed to do is plug the brake controller that is mounted on the trailer into the 7-way connecter at the back of the motorhome. Then plug in the trailer plug to the brake controller that, once again, is mounted to the trailer. I then have a remote gizmo that I plug into a cigarette lighter that wirelessly controls the braking action. So I think I need to have a hot (if that is the correct term) 12v supply that goes into the 7-way plug at the back of the motorhome.
I got this wireless thing because I will also be towing the trailer with my truck as well and the remote can be easily switched between vehicles.

Thanks,

Judy

'06 Inspire 51760

Re: 7-Way Trailer connector

Reply #3 –
Yahoo Message Number: 68872
That is a different controller then I have used. A 12 volts hot with ignition on should be available somewhere in the engine area. No personal experience with our 06'. How big and how much does your loaded trailer weigh? The way to find out if you have a 12 volt hot wire in the connector is with a 12 volt trouble shooting light or meter. Turn on key and touch each terminal. From what I have read it is possible you may have a hot wire.

Leonard

97' Magna 5418

Re: 7-Way Trailer connector

Reply #4 –
Yahoo Message Number: 68873

Judy:

I can only describe what our '05 Inspire has in the way of wiring from CC.
The 7 way was fully wired; unfortunately the wire for the trailer brakes was a full 12V. When I hooked up the trailer each time I applied the brakes the tires on the trailer locked up. Ruined, flat spotted them.
I traced that wire all the way to the front of the rig, forget about using it. I too run a Prodigy, I simply ran a new wire for the controller, clipped the CC supplied connection and capped off the wire - it carries full 12V every time you apply the brakes. The CC circuit runs directly off the brake light circuit which is incorrect for that line on the Prodigy so you cannot use it for the controller.
Otherwise follow the wiring instructions for the Prodigy, it works fine now.
To summarize (as I was confusing I am sure), clip off the existing wire for the brake controller to the trailer at the 7 way leaving enough to conect your new wire, run a new wire from the Prodigy to the connection at the back. While it is possible to run the wire through the center of the coach (as most of the original plumbing and wiring is done) it is a lot of work. I just ran mine underneath using plastic corrugated conduit (any auto parts store) and screw down clamps. Just keep it tight against the bottom; I used 10 gauge wire because of the distance. am sure some voltage is still being lost but more than enough gets back there to operate the brakes on the trailer.
I am sure a pro could have done it better but it was simple and it works.
A word of caution: Be careful about tongue weights. It didn't take much to exceed our rear axle rating. While the hitch can handle 1,000lbs tongue and 10,000 total, there wasn't anywhere near that reserve carrying capacity. Towing a dinghy/toad car is no problem, pulling a heavy trailer with lots of tongue weight might be an issue. The tongue weight is the issue.
I would be concerned primarily with the tires, can they handle the added tongue weight?

Bob (rthandren@...)
'05 Inspire 51178

Re: 7-Way Trailer connector

Reply #5 –
Yahoo Message Number: 68884
Robert, you might want to check out the Prodigy RF on their website, this is what Judy is referring to. It is not a standard wired controller, it's a WIRELESS brake controller, the actual controller is bolted to the trailer, so only a true +12v is needed, not the variable voltage that a normal WIRED brake controller (like an original Prodigy, or the Prodigy P2 or P3). The RF plugs into a standard 7-way pin, and does NOT need a brake controller on the tow vehicle - that's the whole point, it allows you to move a trailer between multiple tow vehicles. The only thing the tow vehicle has is a remote plugged into the cig lighter, showing controller status etc.
I'm going with a standard wired Prodigy P2 (I've heard of some reliability problems with early runs of the P3), I like the reliability of wired, plus I personally don't like having things plugged into cig lighter outlets.
You're of course right, that whether or not the CC is supposed to be wired with +12, Judy should have this checked with a voltmeter or test light. Trailer brakes are too important to mess with to not explicitly verify that everything is fully working as it should, plus there could be corroded connection or blown fuse or whatever.

Jim

Posted by: "Robert Handren" rthandren@... rthandren Sun Feb 27, 2011 5:39 pm (PST)
Judy:

I can only describe what our '05 Inspire has in the way of wiring from CC.
The 7 way was fully wired; unfortunately the wire for the trailer brakes was a full 12V. When I hooked up the trailer each time I applied the brakes the tires on the trailer locked up. Ruined, flat spotted them.
I traced that wire all the way to the front of the rig, forget about using it. I too run a Prodigy, I simply ran a new wire for the controller, clipped the CC supplied connection and capped off the wire - it carries full 12V every time you apply the brakes. The CC circuit runs directly off the brake light circuit which is incorrect for that line on the Prodigy so you cannot use it for the controller.

Otherwise follow the wiring instructions for the Prodigy, it works fine now.

Re: 7-Way Trailer connector

Reply #6 –
Yahoo Message Number: 68886
Thank you for the reply. My wireless brake controller came with a "dummy" 7-way plug that has lights on it to indicate whether a connection is present from turn signals, brakes, to the 12 volt connection. The plug indicated NO 12 volt power to the motorhome plug. So I thought it would be a good question to find out if CC did in fact run a 12v wire to the plug or near vicinity. The same thing happened when I plugged the test plug to the back of my truck, but reading the owner's manual, I found I need to purchase a wiring harness for it. I can find no such answer for the motorhome.

Judy

'06 Inspire 51760

Re: 7-Way Trailer connector

Reply #7 –
Yahoo Message Number: 68889
You will have to have the 12volt hot wire installed on both vehicles. The wiring harness for the truck is for a regular trailer brake install, I believe, and will not send a hot 12 volts to the back. Unless the harness is made especially for the brake control you have. Something for you to check.

Leonard

97' Magna 5418

Re: 7-Way Trailer connector

Reply #8 –
Yahoo Message Number: 68890

Thanks for the clarification Jim, I saw "Prodigy" and assumed it was similar to mine. While I love the idea of fewer wires so many things are going RF (DVRs, etc), while there is plenty of room in the spectrum to avoid interference problems few manufacturers look beyond their own needs. It then becomes the purchasers' problem.
Absolutely on the voltmeter. I did that but had no idea CC would wire it a full 12V any time the brakes are applied. At least the tires were old and in need of replacement anyway. It hurt a bit less after a dumb/quasi dumb event.
The tire smoke was awesome though - I was very popular with other drivers who were enjoying the show. I have more fun ways of making that kind of smoke but that usually invites the local constabularly to visit me and generate undesireable documents.

Bob (rthandren@...)
'05 Inspire 51178

Re: 7-Way Trailer connector

Reply #9 –
Yahoo Message Number: 68891

Judy:

On our rig the only time the brake controller circuit would have turned on is when the brake pedal is depressed. Same for the other circuits, the turn signal will light only when the motor home is flashing its signal, etc. On some setups there is a charging circuit but the vehicle would likely need to be running to see anything. Just plugging the tester into the 7 way doesn't test anything, you need to activate each circuit.
As the 7-way on our Inspire is completely visible near the bottom of the rear skirt you can see whether wires are attached to it. In addition each wire has a number on it identifying the circuit that applies to. There is a list in the owners manual book listing the numbers and what the circuits are. Have you seen any of this?

Am I making sense?

Bob (rthandren@...)
'05 Inspire 51178
 

Re: 7-Way Trailer connector

Reply #10 –
Yahoo Message Number: 68906
? Robert, thanks for pointing this out. I will get out my manual and crawl under there and see what is happening. Fortunately I have a neighbor who is going to check out the circuits for me and is much more knowledgeable how these things work..........

Judy

'06 Inspire 51760