Electric Jack Question

kmtweb

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2020 Alumiduty 7.3
Hey Guys, I ordered a Lippert smart jack with a 7-way plug. I wanted the 7-way plug so that I can just plug into my 7-way to power the jack. Seems like there is no power to the jack. I read the manual, and checked the fuses, but I have no power. Anyone have this problem or is there something that I'm missing? Any feedback would be greatly appreciated. TIA
 
With a multimeter see if you have 12 volts on the pin at 1 o'clock. See attached picture. You will have to measure from black to white. If there is no power it's a blown fuse or other electrical problem. If there is 12 volts present, the jack motor might not be getting enough amps to operate. I know some vehicles have limited current flow from the hot pin. That jack motor requires 30 amps. My old F150 would only allow about 10 amps. You could also power the jack motor directly from a battery to ensure the motor is working properly.
 

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Hey Guys, I ordered a Lippert smart jack with a 7-way plug. I wanted the 7-way plug so that I can just plug into my 7-way to power the jack. Seems like there is no power to the jack. I read the manual, and checked the fuses, but I have no power. Anyone have this problem or is there something that I'm missing? Any feedback would be greatly appreciated. TIA
You probably would need a dc to dc charger to get enough power from the truck. Normally you just wire the jack to your rv battery though.
 
I believe there is something weird where the truck needs to be running and a brake apply has to have happened before you will get power at the 7 way, I would try that.
 
With a multimeter see if you have 12 volts on the pin at 1 o'clock. See attached picture. You will have to measure from black to white. If there is no power it's a blown fuse or other electrical problem. If there is 12 volts present, the jack motor might not be getting enough amps to operate. I know some vehicles have limited current flow from the hot pin. That jack motor requires 30 amps. My old F150 would only allow about 10 amps. You could also power the jack motor directly from a battery to ensure the motor is working properly.
Just wanted to add some additional info. I currently have my travel trailer hooked up to my 2022 F350 7.3l Tremor for a trip this weekend so it was easy for me to do some testing. I have a battery monitoring system on the trailer trailer and my battery is at 50% state of charge. I started my truck while monitoring the current going to the camper through the 7way hot pin and it was a steady 12 amps. I unplugged the trailer from the truck and hooked the trailer into 120v and my trailer battery was charging at 55 amps. Bottom line is that I don't think you will get enough power from the truck through the 7way connector to run the jack motor. If you have a battery on your trailer I would direct wire it to the battery through an inline fuse.
 
Just wanted to add some additional info. I currently have my travel trailer hooked up to my 2022 F350 7.3l Tremor for a trip this weekend so it was easy for me to do some testing. I have a battery monitoring system on the trailer trailer and my battery is at 50% state of charge. I started my truck while monitoring the current going to the camper through the 7way hot pin and it was a steady 12 amps. I unplugged the trailer from the truck and hooked the trailer into 120v and my trailer battery was charging at 55 amps. Bottom line is that I don't think you will get enough power from the truck through the 7way connector to run the jack motor. If you have a battery on your trailer I would direct wire it to the battery through an inline fuse.
Following this as I have the same issue. I sent mine to the dealer and he checked everything and said it's function properly. Power/plug works. I've tried running, hit the brakes during lights on, stand on my head, jump up and down, and nothing works. I was going to go to another person and see if his SuperDuty runs the jack. I'm beyond frustrated as I have to crank my electric jack
by hand.
 
Following this as I have the same issue. I sent mine to the dealer and he checked everything and said it's function properly. Power/plug works. I've tried running, hit the brakes during lights on, stand on my head, jump up and down, and nothing works. I was going to go to another person and see if his SuperDuty runs the jack. I'm beyond frustrated as I have to crank my electric jack
by hand.
Do you not have a battery on your trailer? Direct wire it to the battery and problem solved.
 
Do you not have a battery on your trailer? Direct wire it to the battery and problem solved.
It's the really small one that runs the brakes. I am going to take it to a trailer shop and install a large deep cell one so I can do this. Just hoped I didn't have to with the 7 pin one I purchase. Live and learn I guess.
 
It's probably the "smart tow" feature. On my F150, the 7 pin wouldn't supply power until the truck's computer sensed the 7 pin was inserted and the dash said, "Trailer connected". You might need a resistor or something on the running light pin to trick the truck into thinking there's a trailer connected.

Edit: Yup, that's what it is. This guy fixed it wiring a light in with the brake circuit.
 
It's probably the "smart tow" feature. On my F150, the 7 pin wouldn't supply power until the truck's computer sensed the 7 pin was inserted and the dash said, "Trailer connected". You might need a resistor or something on the running light pin to trick the truck into thinking there's a trailer connected.

Edit: Yup, that's what it is. This guy fixed it wiring a light in with the brake circuit.
Yes, this is correct, it is a smart connector... You just need some nominal load as you figured out...
 
It would be nice if a company created a 7pin to 7pin connector with all of the “trickeration” built in to it. That would solve all of these Smart Truck issues.
 
This is still odd because I run a winch off of my 7 pin. I mounted a winch on the front of my utility trailer and didn't want to put a battery on it so I just wired it to a 7 pin I bought at the parts house. :unsure:
 
Thanks @zimm and @Modman !
Has anyone found a more practical solution to the one shown in the video? Perhaps connecting all the 'other' wires to a single resistor? Or, is the real answer to just run a dedicated wire and just forget about using the 7pin?
 
Thanks @zimm and @Modman !
Has anyone found a more practical solution to the one shown in the video? Perhaps connecting all the 'other' wires to a single resistor? Or, is the real answer to just run a dedicated wire and just forget about using the 7pin?
I have not seen any nicely packaged solutions, although, there may be something out there... I'm thinking something like a 7-way plug with resistors already integrated. I think you still need to hit the brake to get something like this to work, though, so still less than ideal.

The tech on etrailer suggested running an additional power feed with a breaker to the power feed on the truck 7-way to bypass the smart control. Seems like that would work if you wanted to use the 7-way interface, but if you are going thru the trouble of running power from the battery you might as well make a standalone interface with a simple connector. Just my opinion.
 
It's probably the "smart tow" feature. On my F150, the 7 pin wouldn't supply power until the truck's computer sensed the 7 pin was inserted and the dash said, "Trailer connected". You might need a resistor or something on the running light pin to trick the truck into thinking there's a trailer connected.

Edit: Yup, that's what it is. This guy fixed it wiring a light in with the brake circuit.

Thanks for the video. The description in it shows a possible pre-made solution to allow us to trick the truck.

1676479130168.png


 
Thanks @mds2004 - that looks promising. And I have that issue with my TT led lights. Perhaps 2 birds with 1 stone!
 
Another idea- I did this on my Jeep Wrangler where I added the factory tow harness. I wired the 7 pin power to my power accessory relay box which is like an aftermarket up fitter switch set up. I bought a switch labelled "trailer power" and use that to toggle power to the 7th pin. You could do the same on the Ford with an up fitter switch or switch pro box.

What I don't know is if the truck will not detect the trailer if the 7 pin power is cut off from the truck's brain and is hard wired?
 
interesting, got sent to this thread as I am looking to find a powered travel cooler/fridge to run off that plug.
 
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