Open Tailgate - Power Drain?

[wlarsen76]

First-time modern truck owner here — last one I owned was a 2002. Learning the hard way with my 2024 Ranger Raptor.
I was packing up from a camping trip when I tried to start the truck — and got hit with a bunch of error messages. The one that kept repeating was that the emergency brake couldn’t disengage.

I asked ChatGPT, and sure enough, it pointed to a dead battery. My brother gave me a jump, and the truck started right up. Within 10 minutes, the charge was showing 8/18.
I couldn’t figure out what drained it. The only possibilities I came up with:

• A WolfBox digital mirror plugged into the 12V outlet in the console (I confirmed it turns off when the truck is off).
• The tailgate was open all weekend.

I had no idea leaving the tailgate open could drain the battery, but I’ve seen multiple threads saying it can — not directly, but because the truck stays in an AUX or semi-awake state and doesn’t fully sleep.

Can anyone confirm if that’s true?
And is there any way to prevent it or trick the truck into thinking the tailgate is closed?

I like leaving it down while camping, so I’d love a workaround.

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[stuartmunto]

No, leaving the tailgate down should not drain the battery. Even leaving a door open, the system will eventually turn off the interior lights and shutdown all screens etc. The truck even has a low power mode self protection where if the battery is getting low it’ll make sure to turn off all electrical lights and computers so the battery will have enough charge to start again - this means even unlocking or opening the door the lights stay off and the screens don’t even turn on.

You could have a faulty battery, so maybe get the battery checked out?

 

[wlarsen76]

No, leaving the tailgate down should not drain the battery. Even leaving a door open, the system will eventually turn off the interior lights and shutdown all screens etc. The truck even has a low power mode self protection where if the battery is getting low it’ll make sure to turn off all electrical lights and computers so the battery will have enough charge to start again - this means even unlocking or opening the door the lights stay off and the screens don’t even turn on.

You could have a faulty battery, so maybe get the battery checked out?

Okay, thanks for confirming. I will.

 

[wlarsen76]

Okay, I need a second opinion.

I just dropped off my truck at the dealer to investigate a possible power drain. I mentioned that I had a Wolfbox mirror plugged into the 12V (cigarette lighter) outlet in the center console.

The service advisor said he was 98% sure that the mirror was drawing power and causing the battery to die. He added that if that’s the case, I’d need to pay for a parasitic drain test.

My response was: “I’m not sure a parasitic drain test is necessary if the outlet is designed to cut power when the truck is off (there are no other added components). Either it continues to supply power or it doesn’t—that should be easy to confirm.”

So, I’m just looking for a definitive answer:
Does the center console 12V outlet on a 2024 Ranger Raptor supply power when the truck is off?



**Edit**
Coming back as I'm thinking this through.
Why would they even be starting with a parasitic drain test?
The other day, I measured the voltage at 11.28 volts after jumping and driving for 30-40minuts.
I don't think that's normal. I think it should be up around 12v.

So, shouldn't they take this approach?

1. Validate whether or not the console outlet draw power even when the truck is off?
2. Validate the period of time where the truck goes into "sleep mode and should be shutting off?
3. Shouldn't they load test or conductance test the battery first? Check resting voltage is above 12v?
4. Then maybe test the alternator to determine why it doesn't seem to be charging the battery?

Before blaming it on the mirror?

I wonder what happen if they say -- Yup, bad battery -- but we won't pay for it because your mirror ruined the battery.

 

[Bushmechanic]

If by parasitic drain test they just mean checking amp draw when the truck is off, that's normal.

Indeed, that's the first thing I've checked many times.

The only drawback I can think of is losing settings due to disconnecting the battery.

 

[wlarsen76]

I cleaned this up from his text message but this was his response

The technician completed the parasitic draw test — it passed (we ran it under warranty.) He’s now testing the battery itself using Ford’s diagnostic tool, which is very thorough and takes about three hours to complete.
If the battery test fails, it will be replaced. If it passes, the result will indicate that the battery is good but simply needs a charge. Given the timing, this process will extend into tomorrow.

t just occurred to me—if all he does is charge the battery, that still doesn’t explain why the alternator wasn’t charging it properly when I was driving it around. And I still have no idea what drained it to begin with.

 

[Bushmechanic]

I cleaned this up from his text message but this was his response

The test confirmed there was no excess parasitic draw.

That eliminated your mirror as a variable, which is a good thing, for you.

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