Trailer Battery Not Charging

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Jun 22, 2019 | 10:26 AM

phantomqa

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Trailer Battery Not Charging

I did a quick search, but didn't find others with my problem. I have a 2018 SD 6.7 SBCC FX4 Lariat Ultimate and lately (this past week or so) when I power up the truck (not start) the dash display cycles between "Trailer Battery not charging see Manual" and "Full Accessory Power Active". Sometimes it's cycles so fast it takes a bit to read. Goes away after starting and everything seems normal. This is without the trailer being connected. Is there really an issue with the trailer battery charging circuit, or just some kind of software glitch or ??? Any feedback appreciated...
Thanks Dave

Jun 22, 2019 | 10:38 AM

Fordplatty15

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If I recall, the truck has to be running to charge the trailer battery.

Jun 22, 2019 | 11:00 AM

phantomqa

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Quote:

Originally Posted by phantomqa

Here's a short video clip of what I'm seeing. This just started in the past week or so. I've had the truck since Feb and have just over 3k miles on it...

Attached Files

IMG_7469.TRIM.MOV (2.86 MB, 2167 views)

Jun 23, 2019 | 06:26 AM

Chrislorl6211

Mountain Pass

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Quote:

Originally Posted by phantomqa

Here's a short video clip of what I'm seeing. This just started in the past week or so. I've had the truck since Feb and have just over 3k miles on it...

Try going into the menu/trailer settings and deselect the trailer. Tell it no trailer is connected or selected and see if it still happens.
I get a "Trailer not connected " warning each time I start if I do not de-select the trailer, maybe it is looking for it and not seeing it so it is freaking out.

Jun 23, 2019 | 06:50 AM

phantomqa

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Have already de-selected trailer in the menu. Yesterday I noticed this only occurring when I step on the brake in preparation to start??? I'll be reconnection to the 5th wheel in a week and see if this still occurs.

Jun 24, 2019 | 09:12 AM

phantomqa

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I found this in another post. I suspect what I'm seeing is "Normal" without the trailer connected if the brake controller circuit triggers the Trailer charging function???

Quote:

Originally Posted by SUPERTRUCKERS

Here you go! Ford Special Service Message:
SSM 46257

"All 2017 F-Super Duty vehicles equipped with a factory trailer brake controller (TBC) utilize a trailer module (TRM) which initiates the trailer charging system. For trailer charging to operate, the TRM must detect a trailer is connected and a brake pedal input before charging will be present at the trailer connector. Adding the trailer battery charge relay and fuse into the battery junction box are not required to operate trailer charging with a TRM."