Battery Charging Question

[uncle_bob]

Originally Posted by 68 Overlander

Odd indeed Bob. There should be voltage at that charge line pin.

Hi

There's a string of "modules" that control the power to the pin on a new(er) Ford truck. It's no longer a simple process. Some of them figure out that there is a trailer attached (that part works). Others of them hook up power to the pin ( ... not working on my truck ...). Since I'm out and about (and on shore power), we'll worry about that repair at some point in the future.

Bob

[68 Overlander]

Originally Posted by uncle_bob

Hi

There's a string of "modules" that control the power to the pin on a new(er) Ford truck. It's no longer a simple process. Some of them figure out that there is a trailer attached (that part works). Others of them hook up power to the pin ( ... not working on my truck ...). Since I'm out and about (and on shore power), we'll worry about that repair at some point in the future.

Bob

Good answer Bob. My latest Ford was a 08 F350 DRW short box (yes really) that I had (and still own a Lance camper that fits on it) for hunting and fishing. I did lose charging to the batteries and cussed it up and down until I found that fuse was blown. What a difference when I found it. My Lance has a separator (not isolater) and it was never the problem. All along it was that dang fuse under the hood. Being in this industry, I was supposed to know better ha. Le me know what you find in that new Ford. I'm driving my old trusty 97 model manual now and I love it. Not ready for a new truck and still love this old girl

[uncle_bob]

Originally Posted by 68 Overlander

Good answer Bob. My latest Ford was a 08 F350 DRW short box (yes really) that I had (and still own a Lance camper that fits on it) for hunting and fishing. I did lose charging to the batteries and cussed it up and down until I found that fuse was blown. What a difference when I found it. My Lance has a separator (not isolater) and it was never the problem. All along it was that dang fuse under the hood. Being in this industry, I was supposed to know better ha. Le me know what you find in that new Ford. I'm driving my old trusty 97 model manual now and I love it. Not ready for a new truck and still love this old girl

Hi

On my F-250 the "magic fuse" does not exist. Look in the manual and it's supposed to be over here. Look at that location, no fuse, no fuse contacts....hmmm... go on the forums and you find that the fuse was moved after the manual went to print. The *real* fuse is over there ... Indeed AS does *not* have a monopoly on goofy manual issues

Bob

[JMynes]

With my 2017 F250 I have seen 11 amps charging through the umbilical.
I was impressed.
As I understand it, the truck requires a ‘secret handshake’ to energize the charge line. The trailer has to be plugged in, engine running, and the brake pedal depressed once to activate the relay.
The end result is that checking for voltage at the truck socket won’t give voltage, because there is no trailer attached.
Plugging in trailer and starting the engine will fail as well, gotta tap the brake.
I have not verified any of this, it’s just what I remember reading. All I really know is mine works straight off the dealer lot, without adding fuses or relays.

[uncle_bob]

Originally Posted by JMynes

With my 2017 F250 I have seen 11 amps charging through the umbilical.
I was impressed.
As I understand it, the truck requires a ‘secret handshake’ to energize the charge line. The trailer has to be plugged in, engine running, and the brake pedal depressed once to activate the relay.
The end result is that checking for voltage at the truck socket won’t give voltage, because there is no trailer attached.
Plugging in trailer and starting the engine will fail as well, gotta tap the brake.
I have not verified any of this, it’s just what I remember reading. All I really know is mine works straight off the dealer lot, without adding fuses or relays.

Hi

Indeed the various modules do require a bit of this and that to put voltage on the pin. I can monitor the voltage when in motion, towing down the highway. There's noting on the pin in that situation. Once you are at speed, all the handshake stuff is long past ....

Mine worked fine with no fuse or relay changes. It was putting > 18A into the trailer DC/DC converter for a couple trips.... then it wasn't. Fuse went and was replaced. Still no power to the trailer on the pin.

Bob

[TurkeyRun]

Two weeks ago I picked up a 2018 Ford Expedition with a heavy-duty tow package, after my lemon of a Mercedes diesel crapped out 1500 miles from home.
The Ford would not charge the Airstream batteries. Not a big deal for a few days because we were plugging in each night, and I had plenty of other technical details to learn. Eventually I got to the fuse diagram in the manual, pulled the fuse and it was fine. However, after removing and replacing the fuse, it suddenly started charging. Go figure.