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JoeHTP · 07-07-2017, 06:40 PM

We just picked up our new 25' FC yesterday, and are towing it with our 2017 F-150 XLT.

All the trailer lights work perfectly (running, brakes, etc.), but we cannot seem to get any battery charging voltage. As I understand it, prior to 2015, F150s required a relay to power to the charge line, but post 2015, it is a smart connector that is supposed to detect when there is a load on the connection and provide power automatically. No relay.

The trailer towing setup on the dash detects the AS, the only thing not working is the charge line.

Anyone have a clue as to how to solve this?

uncle_bob · 07-07-2017, 07:34 PM

Hi

You probably *are* getting charging from the Ford. There is only just so much you can accomplish charging from the TV. Unless you were driving for 20 or 30 hours (or the battery is totally dead), it's not going to do a whole lot.

Hooking up to shore power *should* charge the batteries in under 5 hours. Solar might do it in a week or so. It depends on how much sun you get.

Also note that you get to 80% long before you get to 90% charge. Getting from 90 to 95 or 95 to 100 takes quite a while.

Bob

**DKB_SATX** · 07-07-2017, 07:42 PM

How are you determining that the charge line isn't working? The batteries aren't at 100% when you arrive? Or you're checking the voltage on the SeeLevel in the trailer while the truck is running? I think it will ONLY charge when the engine is running, and it might take a sec for the truck to energize the line but by the time I've checked the SeeLevel I find it at around 13.6V while the truck is running. Is the trailer in Store or Use when you're checking? Have you metered the 12V pin on the 7-pin to make sure you "see" the battery through the 7-pin?

JoeHTP · 07-08-2017, 03:20 AM

Thank you for the responses.

The dealer installed the hitch and tested..no power. I then read on another forum that because it is "smart", it has to have a load like a battery connected before it will put out any power. However, even connected the Seelevel would show only 12.7 volts (The batteries were not fully charged at the time). I do not recall if the batteries were in store or use, I will have to check again.

I have also read on another forum that vehicle has to be in drive before the power turned on. I can't get out there till Sunday to check these things again .

Quote:

Originally Posted by DKB_SATX

How are you determining that the charge line isn't working? The batteries aren't at 100% when you arrive? Or you're checking the voltage on the SeeLevel in the trailer while the truck is running? I think it will ONLY charge when the engine is running, and it might take a sec for the truck to energize the line but by the time I've checked the SeeLevel I find it at around 13.6V while the truck is running. Is the trailer in Store or Use when you're checking? Have you metered the 12V pin on the 7-pin to make sure you "see" the battery through the 7-pin?

paiceman · 07-08-2017, 04:38 AM

We had an F150 I think it was a 2012 Ecoboost. Ours did not charge, there are two fuse boxes on the F150s. The fuse for the trailer charging, at least on ours, was up front in the engine compartment and there was no fuse in the slot. Put the proper one in, don't remember what it was, and we had charging.

Bud

AnnArborBob · 07-08-2017, 04:47 AM

First, understand that the tow vehicle plug will only provide around 7 to 10 amps of charge (at best) to the batteries so a two hour tow isn't going to do much. Second, check the fuse in the tow vehicle to see if there is one in the slot for charging the trailer batteries. Finally, make sure the "store/use" switch is "use" mode and not store mode or the battery will not charge. If all these fail to resolve the issue, and you can borrow another tow vehicle for a test, try hooking the test tow vehicle to the trailer and see if it's working. It this works, then the problem is with your tow vehicle. If this test does not work, then the problem is with the Airstream.

AnnArborBob · 07-08-2017, 04:49 AM

Also, not sure who mentioned the "smart relay" in post 2015 Airstreams. We have a 2014 and there is no manual relay to get power from the tow vehicle to the trailer so it must be one of those "smart relays."

lsbrodsky · 07-08-2017, 04:53 AM

First in my 2012, the TV charge line is always connected to the battery bus, independent of the STORE switch.
Second, though my truck was a GM, it came with the factory towing package and both the fuse and the 12 v charging line under the hood were disconnected. I had to install the fuse, 30 amp I believe, and connect one wire, well-marked. Then all was well. It was easy to troubleshoot because GM vehicles keep the charging line energized all of the time, requiring you to remember to unplug the 7-way at risk of running down your TV battery.
Larry

overlander63 · 07-08-2017, 07:27 AM

The voltage at the battery on this trailer is "battery voltage", no matter if the truck is running or not, has been driven or not, if the use/store switch is in use or store, if a trailer has been selected in the onscreen menu on the dash or not.
Everything else works except the charge line.
And of course, Ford does not appear to have a wealth of info on how this should be set up, enabled, or adjusted.

https://www.youtube.com/watch?v=T2NsTi_43g4

66coupe · 07-08-2017, 04:24 PM

Quote:

Originally Posted by overlander63

The voltage at the battery on this trailer is "battery voltage", no matter if the truck is running or not, has been driven or not, if the use/store switch is in use or store, if a trailer has been selected in the onscreen menu on the dash or not.
Everything else works except the charge line.
And of course, Ford does not appear to have a wealth of info on how this should be set up, enabled, or adjusted.

https://www.youtube.com/watch?v=T2NsTi_43g4

Check the owner's manual fuse box diagram. In my 2014, and in almost every 150 whose owner I know, Ford followed a practice of deliberately leaving the fuse that controls charging out of the fuse box, stashed somewhere in the truck -- glove box, cup holders or (in mine) in the cup holder in the forward portion of the drivers' door. As a long term practice by Ford, I can only figure they do it to ensure no power or any kind is conveyed to the plug under the rear bumper. My truck powered the lights but would not charge. If the fuse is in the correct slot in the fuse box and the truck still will not charge the battery, some of the other suggestions above may apply. 66 coupe

overlander63 · 07-08-2017, 08:41 PM

Quote:

Originally Posted by 66coupe

Check the owner's manual fuse box diagram. In my 2014, and in almost every 150 whose owner I know, Ford followed a practice of deliberately leaving the fuse that controls charging out of the fuse box, stashed somewhere in the truck -- glove box, cup holders or (in mine) in the cup holder in the forward portion of the drivers' door. As a long term practice by Ford, I can only figure they do it to ensure no power or any kind is conveyed to the plug under the rear bumper. My truck powered the lights but would not charge. If the fuse is in the correct slot in the fuse box and the truck still will not charge the battery, some of the other suggestions above may apply. 66 coupe

We had checked for relays and fuses, and in the grand tradition of Murphy's Law, the owner's manual and packet had been left at home. That's where I usually find the relays and fuses. Without any kind of documentation, a wrong guess can become very costly. In the end, since all the lights and the brake controller (factory) functioned correctly, and the only thing not working was the charge line feed, we decided to let the trailer leave, and for Joe to give his local Ford dealer a call to get some further guidance.

HiJoeSilver · 07-08-2017, 10:23 PM

Redesigned in 2015 on. The old fuses and relays are gone. You won't read voltage on the charging post on the outlet of the 7 pin plug on the back of the truck. The trailer has to be connected to the truck and the truck has to be running. Then you have to tap the brakes so the truck can realize that your trailer is connected. When the truck realizes the truck is connected to the trailer (trailer connected message on dash) and the truck is running it will then send voltage to the trailer charging line. The stock wire on the new F 150s is only 18 gauge so it'll only give you enough to help keep the battery charged, not much else.

Hope this helps.

HiJoeSilver · 07-08-2017, 10:30 PM

A way to check is to read the voltage positive to negative in the trailer when it's disconnected, usually you'll see 12.6-12.9 volts. Plug the trailer in and start the truck, tap the brakes to get trailer connected status and check voltage again. You'll usually see 13.5-14v since the alternator will now be supplying voltage to the trailer.

HiJoeSilver · 07-08-2017, 10:36 PM

Most dealers don't have a clue about this.

It is possible to add a new charging wire, heavier gauge, a few fuses and a relay and provide higher current than the 18 gauge wire allows but that's a bit more work.

uncle_bob · 07-09-2017, 09:24 AM

Hi

Even if you do go with a fat wire to the connector, you still have the charge system in the truck doing it's thing. Read the various threads on how "essential" a super duper charger / converters and compare that to what your alternator is doing ....

Bob

MelGoddard · 07-09-2017, 01:44 PM

Quote:

Originally Posted by HiJoeSilver

Redesigned in 2015 on. The old fuses and relays are gone. You won't read voltage on the charging post on the outlet of the 7 pin plug on the back of the truck. The trailer has to be connected to the truck and the truck has to be running. Then you have to tap the brakes so the truck can realize that your trailer is connected. When the truck realizes the truck is connected to the trailer (trailer connected message on dash) and the truck is running it will then send voltage to the trailer charging line. The stock wire on the new F 150s is only 18 gauge so it'll only give you enough to help keep the battery charged, not much else.

Hope this helps.

I have a 2015, Super-Crew, Eco-boost, and in my vehicle manual, there is no trailer power fuse listed. (Everything else is there.)

I haven't tried the above yet, (until i'm hooked up for the next trip), but I have no idea if there is a 30 amp fuse 'somewhere' for this function.
Anybody know where one might be???

JoeHTP · 07-09-2017, 05:24 PM

Thank you for all the feedback and suggestions. I had an opportunity to go out and try things today. Nothing worked.

With the trailer in use, I connected the 7-pin connector and powered up the truck. Checked voltage with a meter across the batteries..no change from without the connection. Did the same in Drive. No deal.

I am going to contact Ford to have them check out the circuit.

Joe

uncle_bob · 07-10-2017, 10:28 AM

Quote:

Originally Posted by JoeHTP

Thank you for all the feedback and suggestions. I had an opportunity to go out and try things today. Nothing worked.

With the trailer in use, I connected the 7-pin connector and powered up the truck. Checked voltage with a meter across the batteries..no change from without the connection. Did the same in Drive. No deal.

I am going to contact Ford to have them check out the circuit.

Joe

Hi

Have you gone through the entire "set up the trailer" process on the screen in the cab? Does the truck recognize the trailer (report it on the screen) when you hook it up? That's what has to happen in order to get power to the 7 pin.

Bob

JoeHTP · 07-13-2017, 12:12 PM

Yes, the trailer is set up and recognized. Had a chat with Ford and they are going to have a look when I bring it by.

Joe

JoeHTP · 07-24-2017, 02:09 PM

I think I figured out what may have happened. When I picked up my AS, the batteries were not fully charged (due to another problem - I think the batteries need to be above a certain voltage. As suggested,the brake has to be tapped and the vehicle has had to be in drive for the power to kick on. If I do that, my battery meter shows 13.4 volts.

However, due to the problem with the charging before I picked it up, I do not think the batteries are fully up to speed.

Joe

Quote:

Originally Posted by JoeHTP

Yes, the trailer is set up and recognized. Had a chat with Ford and they are going to have a look when I bring it by.

Joe