7 Pin Connector - No Power at Aux connection

[CJ4812]

I am hoping I can get some troubleshooting advice for the 7 pin connector at the back of my coach.  When my toad was set up to be made towable, I had a battery charger installed so I wouldn't have to worry about the toad battery going dead while driving from my blue ox braking system.  The line from the batter charge goes to the auxiliary port on the 7 pin connector of the toad.  After a long day of driving the car battery is dead and will need to be jumped to bring it back to life.  The mechanic who installed the battery charger tested the 7 pin connector on the coach and there isn't any power to it when the coach engine is running.  I thought the aux connection would be hot when the engine is running to provide a charge to the car battery.  It came from the factory like this.  2017 Coachmen Pursuit F53 chassis.  He thought maybe a fuse was never installed allowing power to run to the 7 pin connector on the back of the coach.  Could he be right?  Is there anything else I could check?  Thanks in advance for the help.

 

[Alfa38User]

Yes, he could well be right!! Why did he not fix this when he installed the charger, did he not test his work??

 

[Rene T]

I would remove the back of the receptacle and check all the screws to make sure they are tight and there's no corrosion on the screws or wires. Corrosion is a common problem but I wouldn't think a fairly new RV would have that issue but you never know.

 

[CJ4812]

I only gave him the car and components to install.  There isn't enough room at his shop for the coach.  He never had the coach at his shop to test the entire system after the install in the car.  It wasn't until a few weeks later when I was on a long trip did I realize the car battery wasn't getting charged.  Last week he came to my house to test the coach and that's when we discovered we weren't getting any power to the connector on the coach side. 

 

[CJ4812]

I would remove the back of the receptacle and check all the screws to make sure they are tight and there's no corrosion on the screws or wires. Corrosion is a common problem but I wouldn't think a fairly new RV would have that issue but you never know.

I'll check this out.  Thanks for the tip.  The RV was bought new over the winter and I brought it home in May.  Hopefully it's something as simple as that. 

 

[mel s]

I only gave him the car and components to install.  There isn't enough room at his shop for the coach.  He never had the coach at his shop to test the entire system after the install in the car.  It wasn't until a few weeks later when I was on a long trip did I realize the car battery wasn't getting charged.  Last week he came to my house to test the coach and that's when we discovered we weren't getting any power to the connector on the coach side.

CJ4812
Why didn't he fix it when he came to your house?
If he won't fix it, and if you can't fix it yourself, I suggest you find a shop with enough room for your coach and have them fix it.

 

[CJ4812]

CJ4812
Why didn't he fix it when he came to your house?
If he won't fix it, and if you can't fix it yourself, I suggest you find a shop with enough room for your coach and have them fix it.

He didn't fix it because it was the end of the day.  Not enough time.  He only came to help me troubleshoot the issue.  He only worked on the car portion originally and I paid him for that.  If I want him to figure out the issue with the coach and repair it I would have to pay him or take it back to the dealership.  By having him over I now know the issue is with the coach and not the car.  I wanted to ask for help from this forum before I pay to have him or someone else figure out the issue.  I was hoping the hear a few suggestions I could try and not have to pay anyone.  The advice from here is always really good...and free.   

Different question - Should this be covered under the original warranty?  I bought this unit in January of 2018. 

 

[Rene T]

He didn't fix it because it was the end of the day.  Not enough time.  He only came to help me troubleshoot the issue.  He only worked on the car portion originally and I paid him for that.  If I want him to figure out the issue with the coach and repair it I would have to pay him or take it back to the dealership.  By having him over I now know the issue is with the coach and not the car.  I wanted to ask for help from this forum before I pay to have him or someone else figure out the issue.  I was hoping the hear a few suggestions I could try and not have to pay anyone.  The advice from here is always really good...and free.   

Different question - Should this be covered under the original warranty?  I bought this unit in January of 2018.

I would think it should be covered. Just check your contract. It may be that all you need to do is make a call to the service department and they may say it's just a fuse missing which may be normal from the factory and they'll tell you where it should be.

 

[regval]

It's my understanding that the Aux 12V wiring to the 7pin connector on the F53 chassis is classified body builder responsibility, ie, not wired by Ford from the factory. So, the coach builder "may" or "may not" install the power wire from a fuse panel to the rear coach 7pin connector.  I'd first call Coachmen and inquire if connection of the auxiliary 12V power wiring to the towing plug is part of the build of the coach. Then, start from there with your troubleshooting.
Good Luck

(EDITED)
Here's a link to the ford F53 owner's manual:  http://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2017-Ford-Motorhome-Owners-Manual-Version-1_om_EN-US_03_2016.pdf

Page 75 lists several "body builder" fuses - one is a 20A (Fuse 16) for a 12V feed. This may be the fuse that would be used to send 12V out to the tow connector. Fuse panel location is described  in the attached document.

 

[CJ4812]

Thank you so much for the help and information.  This site is amazing with the amount of knowledge that is available. 

 

[CJ4812]

It's my understanding that the Aux 12V wiring to the 7pin connector on the F53 chassis is classified body builder responsibility, ie, not wired by Ford from the factory. So, the coach builder "may" or "may not" install the power wire from a fuse panel to the rear coach 7pin connector. I'd first call Coachmen and inquire if connection of the auxiliary 12V power wiring to the towing plug is part of the build of the coach. Then, start from there with your troubleshooting.
Good Luck

(EDITED)
Here's a link to the ford F53 owner's manual:  http://www.fordservicecontent.com/Ford_Content/Catalog/owner_information/2017-Ford-Motorhome-Owners-Manual-Version-1_om_EN-US_03_2016.pdf

Page 75 lists several "body builder" fuses - one is a 20A (Fuse 16) for a 12V feed. This may be the fuse that would be used to send 12V out to the tow connector. Fuse panel location is described  in the attached document.

I called Coachmen.  Sure enough the line is not run to the 7 pin connector as part of the build.  He recommended running a line from the chassis battery to the connector with a 15A, 12V mini breaker installed instead of going from the fuse panel.  What are your thoughts on that vs going from a fused location? 

 

[regval]

I called Coachmen.  Sure enough the line is not run to the 7 pin connector as part of the build.  He recommended running a line from the chassis battery to the connector with a 15A, 12V mini breaker installed instead of going from the fuse panel.  What are your thoughts on that vs going from a fused location?

My suggestion is to run a direct line from the battery as suggested using a 30 or 40A auto-reset circuit breaker. You can find suitable breakers on-line that mount to a chassis rail or metal panel, etc,  via self-tapping screws and have an input and output lug. Find a location near your battery connection to mount the breaker and run a short wire from the breaker to the  battery. The longer load wire going back to the 7pin connector would then be protected as well as the load going out to the towed vehicle. Mounting the breaker near the 7pin plug exposes the long under-coach wire run to possible overload/fire risk. Hope this makes sense.

 

[Rene T]

That all makes sense to me. The only thing I would do any different is go to the back of the receptacle and see if there is a wire there by chance. If there is, trace it forward to see where it goes. If there isn't one, run one as stated. Let us know what you find.

 

[CJ4812]

I found this from Amazon.  I assume this is the correct breaker?  https://www.amazon.com/Auto-Reset-Circuit-Breaker-Bracket/dp/B077W23SJG

I also did a Google search for breakers and there are Type I, Type II.  I don't know the difference between them.  Is this anything I should be concerned about or is the one I have in the link above good enough for what I am doing? 

 

[regval]

I found this from Amazon.  I assume this is the correct breaker?  https://www.amazon.com/Auto-Reset-Circuit-Breaker-Bracket/dp/B077W23SJG

I also did a Google search for breakers and there are Type I, Type II.  I don't know the difference between them.  Is this anything I should be concerned about or is the one I have in the link above good enough for what I am doing?

The one you show is suitable for the purpose. These are typically seen on travel trailers and some cargo trailers and are used to protect the 12V battery feed from the battery to the trailer.  Since your purpose, I believe, is to provide a 12V source to a towed vehicle to charge the vehicle battery, this will provide sufficient current to a battery with a low charge condition. Be sure that the wire you choose to run for this purpose can safely carry the current. The length and gauge are important. Consult a wire gauge chart once you have calculated the length of wire needed.

 

[Rene T]

The one you show is suitable for the purpose. These are typically seen on travel trailers and some cargo trailers and are used to protect the 12V battery feed from the battery to the trailer.  Since your purpose, I believe, is to provide a 12V source to a towed vehicle to charge the vehicle battery, this will provide sufficient current to a battery with a low charge condition. Be sure that the wire you choose to run for this purpose can safely carry the current. The length and gauge are important. Consult a wire gauge chart once you have calculated the length of wire needed.

Any idea why one stud/post is copper and the other is plated steel?  Does it make a difference which post you use for the wire coming from the battery?

 

[mel s]

Any idea why one stud/post is copper and the other is plated steel?  Does it make a difference which post you use for the wire coming from the battery?

Rene T
For the wire coming from the battery you need a plus/positive wire connection... (whether it's copper or plated steel makes no difference).

 

[Lou Schneider]

The copper post goes to the battery - you can faintly see BAT below the post in the picture.

The difference is in the way the contacts open when the breaker trips.  You want the DC current flowing from the BAT to the LOAD terminals when the breaker opens, not the other way around.

 

[Rene T]

The copper post goes to the battery - you can faintly see BAT below the post in the picture.

The difference is in the way the contacts open when the breaker trips.  You want the DC current flowing from the BAT to the LOAD terminals when the breaker opens, not the other way around.

Thanks Lou but is still doesn't tell me why 1 is copper and the other is steel. Maybe it's something inside.

 

[regval]

The studs may be the same material, just color coded for identification. When color coded, the power source (battery, supply, etc) should be attached to the copper colored stud or terminal and the load is attached to the silver. Color coded terminals on a dc breaker indicate some internal arc suppression is included, and to be effective, the current flow direction is important. There's a standard that specifies the color coding, but I've long ago stored all my references in the basement archive. The breaker will work even if wired incorrect, but I usually assume the battery is attached to the copper stud when troubleshooting.