12V power outlet is ON all the time (CX-5 2016). Not good :(

TommyW

Member
:
Mazda CX-5 GT 16, Mazda CX-9 07
I am really concern about 12V power outlet; just found out is ON all time, even though car is off. I ordered cell phone charger and LED light is ON all the time. Just worry about the battery if the charger is left 24/7.
What do you think guys?
 
I've had a battery charger w/led plugged in since day one. No issues. I have even gone a few days without driving it.
 
There's a thread in the how tops about switching out the fuses to make it powered off with the car. I was concerned at first too but it once I calculated how slowly a charger would drain it I didn't worry anymore. Just done leave sEthing with a real draw on it
 
If you're looking for a switched 12V outlet, use the one in front of the shift lever.
 
You're talking about an infinitesimal current draw from simply leaving a charging adapter plugged in. If you weren't driving the car for weeks or storing it, it might be a concern. Otherwise, it is a non issue.
 
Why not use the USB port for charging? Or is it slower?
Because most car chargers for cell phone are designed to use 12V cigarette lighter outlet. USB port supplies 5V. In theory, 12V is a little bit more efficient and faster than 5V while charging.
 
Because most car chargers for cell phone are designed to use 12V cigarette lighter outlet. USB port supplies 5V. In theory, 12V is a little bit more efficient and faster than 5V while charging.

Well, maybe. You need to look at the output of the charger. Typically cigarette lighter chargers with USB only have a total output of 5V, so you may as well use the built in USB on the vehicle.

You should also consider that charging a battery at a higher output than designed will only decrease its lifespan. While it may charge faster, there is a trade off. Some devices, like my iPhone 5 will not draw more than 5V even when using the 12V iPad charger (verified with a killawatt)
 
Also, don't devices like iPhone stop drawing power when they reach full charge?
 
Why not use the USB port for charging? Or is it slower?
Because most car chargers for cell phone are designed to use 12V cigarette lighter outlet. USB port supplies 5V. In theory, 12V is a little bit more efficient and faster than 5V while charging.
Well, maybe. You need to look at the output of the charger. Typically cigarette lighter chargers with USB only have a total output of 5V, so you may as well use the built in USB on the vehicle.
You should also consider that charging a battery at a higher output than designed will only decrease its lifespan. While it may charge faster, there is a trade off. Some devices, like my iPhone 5 will not draw more than 5V even when using the 12V iPad charger (verified with a killawatt)
We're talking about the voltage, not current which combines with voltage (wattage) to determine how fast the charger can charge the device. Not only cell phone car chargers designed for 12V cigarette lighter outlet has different plug, but also it take 12V input. The charger then converts 12V to 5V and charges the cell phone as most cell phones use 5V. It doesn't mean 12V charger will charge your cell phone with 12V which will burn your cell phone! The OP has a charger for 12V outlet, and actually he can use switched USB port to charge his cell phone directly with a proper USB charging cable as most cell phones take 5V.
 
So, in regards to the OP's concern...
I had a charger with an LED indicator plugged into my SHOs unswitched 12V outlet from the day I took ownership. And I let it sit undriven for weeks at a time. Non issue.
 
I guess i need to purchase no LED 12v usb charger.
Thank you guys for your responses.

Great forum, great people.
 
I guess i need to purchase no LED 12v usb charger.
Thank you guys for your responses.

Great forum, great people.
No, you really don't. A cell phone charger LED dissipates less than 10 mW of power. Compare it to the starter motor, which a typical starter motor uses about 1 kW. That's about factor of 100,000 difference. Since you can usually start your car several times without recharging the battery with the alternator, I would imagine the battery discharges more to parasitic losses and electrical components that remain on with the car off than to the LED on your charger.
 
I guess i need to purchase no LED 12v usb charger.
Thank you guys for your responses.

Great forum, great people.

I wouldn't. After all, your engine immobilizer circuit flashes an LED 24x7 and you can go months before you'd notice it. The lithium battery in cell phones is 3.8v or thereabouts. 5V from a USB port is enough to charge it 'if the amperage is sufficient.

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One of these will measure voltage and amps from a USB source - if you're curious.
 
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I guess i need to purchase no LED 12v usb charger. Thank you guys for your responses. Great forum, great people.
No, you really don't. A cell phone charger LED dissipates less than 10 mW of power. Compare it to the starter motor, which a typical starter motor uses about 1 kW. That's about factor of 100,000 difference. Since you can usually start your car several times without recharging the battery with the alternator, I would imagine the battery discharges more to parasitic losses and electrical components that remain on with the car off than to the LED on your charger.
Yeah, you don't need that. You only need a USB charging cable and use the switched USB port in the front console cubby to charge your phone. If you have an iPhone, get a cable like the original charging cable that will do it.
 
I am really concern about 12V power outlet; just found out is ON all time, even though car is off. I ordered cell phone charger and LED light is ON all the time. Just worry about the battery if the charger is left 24/7.
What do you think guys?

Ive left my charger in the socket since day one. It's always on. I like it because my phone is always at 100%. (I have a job that forbids cell phones in the facility)
 
Thx for all responses.
This really great forum. Im glad I didn't get a crv2015. Cx5 drives and handles way better.
I will stay with my LED charger :)
 
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