Will leaving the trunk open drain the battery?

Hello everyone !

I am taking my 2021 cx5 camping this weekend, and will most likely have the trunk open for an extended period of time. How do I ensure every light is turned off and my battery doesn’t die?

Thanks In advanced!
 
There's a little switch somewhere back there. I remember turning mine off right after I took delivery.
For the front overheads the switch should be in the front near the rear view mirror.
 
Hello everyone !

I am taking my 2021 cx5 camping this weekend, and will most likely have the trunk open for an extended period of time. How do I ensure every light is turned off and my battery doesn’t die?

Thanks In advanced!
The vehicle has a battery saver. It will turn off the interior lights after about 1/2 hour leaving sufficient juice to restart. Been there, done that when I left a door ajar. The problem is the vehicle issues a high pitched whine as an alert that it is in battery saver mode which would be annoying if you're thinking of tailgating or whatnot.

Even if you figure out how to turn off all the lights you should test whether merely having the door open puts it in battery saver mode issuing the whine. The 2020 manual says only lights-on engages battery saver but I wouldn't necessarily trust that especially if you have a garage for a simple test.
 
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The vehicle has a battery saver. It will turn off the interior lights after about 1/2 hour leaving sufficient juice to restart. Been there, done that when I left a door ajar. The problem is the vehicle issues a high pitched whine as an alert that it is in battery saver mode which would be annoying if you're thinking of tailgating or whatnot.

Even if you figure out how to turn off all the lights you should test whether merely having the door open puts it in battery saver mode issuing the whine. The 2020 manual says only lights-on engages battery saver but I wouldn't necessarily trust that especially if you have a garage for a simple test.
Thanks! On the dash screen it shows the the trunk is open is this a concern or anyone know how to turn this off?
 
may be manually lock the latch mechanism after you open the trunk. This should shut off the light on the dash and trick the car the trunk is closed.
There should be also a way to manually unlock it when you are ready to close the trunk.
 
On my 2016.5 CX the hatch light has a multi-position switch. In one position the hatch light only comes on when the hatch is opened. In the other position the light never comes on, no matter what the hatch is doing.
 
It would take a long ass time for the trunk light to kill your battery. You are over thinking this.
 
A month after I bought my 2021 CX-5 and was detailing the car, leaving the trunk open. After about an hour or so, I heard a couple of beeps and shortly thereafter, when I went to start it up, battery was dead. Dealer said that this was a function of the power liftgate. Dunno, but I do know that I won't leave the trunk open for any more than I have to.
 
I have a 2016.5 CX-5 and I take is camping all the time, with my booster cables because it's ALWAYS dead after 3 days. I have the hatch light off, I tried locking all the other doors, nothing works. The computer keeps looking for the keys or something of the sort. Even tried leaving the fob in the little rectangular cubby that looks like it's made for that purpose, but the battery is always drained if I leave the hatch open all day long for 2-3 days straight. If someone has a solution to this, hack of the programming, anything, I'm all ears
 
In my experience, it does seem to drain the battery pretty quickly. I was cleaning my 2022 CX30, which I've only had for about a month, and left the hatch open for at least an hour.
When I got in to start it and put it back in the garage, I got a screen warning that I need to 'run the car for a while' to recharge the battery.
 
.... The jump starting guy was really surprised that a couple of hours on blinkers killed it
The days of lights (and utilities) being wired up in a simple circuit of switch, fuse, ground, and light are long gone. On modern vehicles, virtually everything electrical is controlled by some type of electronic module. And an active control module is also likely to continue trying to communicate with other modules via CANBUS.

So there's more going on electrically than just the light itself, all putting additional draw on the battery. And even if the light or utility has been programmed to be turned off after a certain amount of time, the mechanical switch still being on may very well prevent that control modules from shutting down (and perhaps others as well).

Although computer modules may not pull very much, even that small draw would nevertheless drain the battery faster than if everything was completely shut down. Parasitic draw testing would be required, in order to determine exactly how much extra draw (if any) is taking place for any given situation.
 
2018 CX5. Sometime during the evening my trunk opened itself(most likely a keyfob accident), it was open all night til morning so approximately 12 to 14 hours. Some tools were missing(by neighborhood thieves) but the battery started right up. And lights were off so they must have auto shutoff.

Have also have been at drive-in theaters for hours with open trunk and no problems.

The overly sensitive keyfob is one of my big problems with this vehicle. Luckily i've caught it other times before it was open too long outside stores, home ,etc.
 
2018 CX5. Sometime during the evening my trunk opened itself(most likely a keyfob accident), it was open all night til morning so approximately 12 to 14 hours. Some tools were missing(by neighborhood thieves) but the battery started right up. And lights were off so they must have auto shutoff.

Have also have been at drive-in theaters for hours with open trunk and no problems.

The overly sensitive keyfob is one of my big problems with this vehicle. Luckily i've caught it other times before it was open too long outside stores, home ,etc.

Wow, that sucks! You're lucky that it didn't rain.
 
Wow, that sucks! You're lucky that it didn't rain.
Lol. Yeah. It's a seldom traveled side street. You dont expect your neighbors to be thieves. But there one guy that roots through peoples trash during his morning walks. Luckily didnt have too many tools in the trunk. They really need to redesign the damn keyfobs. Shouldnt have to worry your trunk will open while your walking around with keys in your pocket.
 
This makes me glad that the 2016's don't have the option of a powered lift gate.
 
This makes me glad that the 2016's don't have the option of a powered lift gate.
Yeah what sucks is it is a mazda design problem with the keyfob.
The liftgate isn't the problem the keyfob is.
Never had keyfob liftgate problems with fords or nissan. Even the Jeep rental I had, didnt have the keyfob accidently trigger liftgate.
 
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.... They really need to redesign the damn keyfobs. Shouldnt have to worry your trunk will open while your walking around with keys in your pocket.
Wondering out loud if it might be possible to build a tiny ridge around the liftgate opening button. The idea would be to create a bit of a recess for that button, so that incidental contact would no longer cause it to activate.

No idea what substances stick well to this type of plastic, so you would need to experiment. Of the various products I've used, the following come to mind for adhering to just about anything: fiberglass resin; Scotch-weld 4799; and B-7000. But perhaps regular superglue, plastic epoxy, or others would work equally well. Regardless of what's used, it wouldn't take very much of it to create a low ridge

From reading posts in other threads, I think your fob is quite a bit different than mine, so I don't know if doing something like this is possible to do on your fob. But in any case, I think you should try to do something about this issue, because one day it might come back to bite you in the butt.
 
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