Where is the fuse for 12v at the seven pin trailer connector

[moejean]

I am looking for the fuse for the 7 pin trailer connector at the rear of the MH. It is a 2011 Sightseer and it is wired for it but there is no power. Does the key have to be on and the MH running or is there power there all the time.

Thanks, Moe

[Mr_D]

I'm about to rewire our '02 DSDP since I'm needing a charge line to the Honda Ody. On ours it's supposed to be wired but, the same as yours, no power at the socket. However, we have a DP so it's just a short run from the chassis (Spartan MM) to the socket. Have two 30 amp auto reset breakers, one goes on the MH side and the other on the towed since a short can happen on either end. Using 10 Ga wire since total length is less than 15'. In fact I just finished rewiring the Sterling towbar last night. Need to finish the MH and van though before the 4th!
On a gas rig your wire may need to be even larger due to the run, just be sure there are fuses at either end. The auto reset I bought online for $1.35 each. The one problem is they have exposed terminals so if something falls across the input side and the frame there could be direct short so I'll have to put some insulation on them. Maybe an old bicycle inner tube and a couple wire ties will do it.

[Bryan H]

My DP has a hidden fuse box behind a panel in the electrical bay that contains the 7-pin receptacle fuses (and a few others). I found it by turning a flasher on and listening for the flasher relay clicking.

[Hikerdogs]

Originally Posted by moejean

I am looking for the fuse for the 7 pin trailer connector at the rear of the MH. It is a 2011 Sightseer and it is wired for it but there is no power. Does the key have to be on and the MH running or is there power there all the time.

Thanks, Moe

Which of the 7 pins are you trying to find power on?
1. The charge wire for the battery only has power when the ignition switch is on.
2. The one for the lights only has power when the coach parking or headlights are on.
3. The 2 for the brake lights only have power when the brake pedal is depressed, or when the 4 way flashers are activated.
4. The 2 for the directional lights only have power when the ignition switch is on and the turn signal lever is in the proper position.
5. The backup light pin only has power when the ignition switch is on and the transmission is in reverse.
6. The pin for the trailer brakes only has power when the igntiton is on, a trailer brake controller is installed, and the brake pedal is being depressed. Some model brake controllers also have to detect deceleration of the vehicle in addition to all the afore mentioned prerequisites. If you have this type controller you'll have a hard time diagnosing the problem if the coach is stationary in the drive.

Here's a wiring diagram for a typical 7 pin trailer socket.
Trailer Wiring Diagrams | etrailer.com

Having said all this there is a fuse and 2 relays for the brake/directional light circuit in the fuse box. On our motorhome the fuse is #22 and the 2 relays are the left 2 in the relay block below the fuse block.

I just went through a lengthy diagnosis of non working brake and directional lights at the trailer socket. It turned out to be a bad connection where the relay ground wires are spliced into the wiring harness between the relay block and the firewall plug. What really complicated things was the fact that all the lights worked on the motorhome. Only the brake/directional pins at the trailer socket were dead.

[1ciderdog]

Originally Posted by Bryan H

My DP has a hidden fuse box behind a panel in the electrical bay that contains the 7-pin receptacle fuses (and a few others). I found it by turning a flasher on and listening for the flasher relay clicking.

That is the same location as on my 2004 Journey.

[Hikerdogs]

The 2011 Sightseer is built on a Ford F53 gas chassis. Ford extends the wires for the trailer connector to within about 3' of the end of the frame rails. All the wires are clearly identified as to which functions they perform. Winnebago extends the wires to the trailer hitch socket they provide at the rear of the coach. On this particular chassis there is no need to extend any additional wires or look for any hidden fuse box. All the wires have been already run and all the necessary fuses and relays are installed in the panels below the dash to the left of the parking brake.

[grtharris]

The +12VDC for the trailer battery is not supplied by Ford it is supplied by Winnebago. On the Sightseer there is a breaker labeled Trailer Battery in a breaker panel low and to the left of the instrument panel. The +12VDC is fed from the breaker through a relay to the trailer plug.

[Hikerdogs]

Originally Posted by grtharris

The +12VDC for the trailer battery is not supplied by Ford it is supplied by Winnebago. On the Sightseer there is a breaker labeled Trailer Battery in a breaker panel low and to the left of the instrument panel. The +12VDC is fed from the breaker through a relay to the trailer plug.

I stand corrected. When I took the Ford wiring harness apart to check the connections to the trailer socket the wire for the 12V power was in the harness. I "assumed" it was just another wire provided by Ford. Further investigation revealed as grthassis said the wire was provided by Winnebago. I think Winnebago ran the wire through the Ford harness just to fool me. It worked.

[grtharris]

Hikerdogs, Yet, strange Ford puts the +12VDC wiring on all there Trucks but not the motorhome chassis.

[Hikerdogs]

Over the years I've had 7 Ford trucks. I ordered them all with the trailer towing package and the last 3 came with a 7 pin trailer connector. When I tried towing one of the trailers with electric brakes behind my 1999 nothing worked. I took it back to the Ford garage and they told I needed to buy $100.00 worth of relays. When I told them I had ordered the trailer towing package they bit the bullet and absorbed the cost. About a month later I was searching through the console and found a bag of relays and fuses. Apparently they were supposed to be installed by the dealer as part of the predelivery setup. When I sold the truck I gave them to the new owner. He probably still has them stashed away in the console "just in case".