Living with the 16v LV battery

[TheTinRam]

Since its purpose is to open the frunk when it is locked due to a dead low-voltage battery, you must obviously not put the emergency battery in the frunk.

The connectors for emergency power are under the lid in the front bumper. That's where I put the battery.

It is a small 12 V battery, a bit bigger than AA size. Found it on Amazon. I don't know the type any more.

Right, the small battery gets placed under that small lid, which will allow you to open the frunk. But what do you do once the frunk is opened? Need something to boost the LV battery enough to power on the systems to put it into tow mode etc. This is where I am debating between a battery powered jump starter, or a small LifePO4 battery.

 

[Darmie]

Happy to help. Yes, it would not be good to pin the 12v out if using the battery. Likekly wouldn't hurt brake servos. Mind you the stepdown transformer I showed would work just fine. Or thought I showed. Maybe in a different thread.

Here is a step down transformer that should work very well:

https://www.amazon.com/gp/product/B09T9ZJSWH/ref=ox_sc_act_title_1?smid=A2B1LC74DVEKDL&th=1

These are good solutions and all but why didn't Tesla create a 16V battery that acks like 12V and just use something like this in their batter module?

 

[frankvb]

The problem with these converters (not technically a transformer) is that they consume power when unused.

Indeed it's a DC-DC converter. They will consume some power when nothing is connected to the output side, but it's not significant. You'd need the specific IC spec but I don't think it will be more than a few tens of mA (maybe up to 100 mA).

Some have an enable line which would allow shutting down to below a few mA.

 

[hgmichna]

How does a Tesla provide 12 V for a trailer? Or does it just use 16 V as well, ignoring any specifications?

 

[TomB985]

How does a Tesla provide 12 V for a trailer? Or does it just use 16 V as well, ignoring any specifications?

It provides ~15v to the trailer plug for the lights, and the +12v battery charging circuit is not used.

 

[A2be]

This thread, from 2022 [Power Inverters for newer 16V Outlet Cars] is proof that the higher 16 V output is preventing a lot of the older power inverters from working.

In addition to the info in that thread, I can report that the older power inverter I had bought for my Model 3 in 2020, and worked fine with the older batt in that Model 3, would not work at all with the higher voltage 16V Li-ion battery in my 2022 Model Y.

So the higher voltage, is non standard, and clearly there are a lot of 12 Vdc accessories sold that won't NECESSARILY work at the higher 16 V nominal voltage of the newer Li-ion battery Tesla uses now.

 

[TheTinRam]

For a tire inflator, I ended up buying this AVID POWER Tire Inflator. It has a battery and 12v connection like my other one but this one works with the 16v outlet. It's also quieter and has a better display. I like it.

 

[dmurphy]

So for those of you looking for jump starters or frunk popping batteries …

Just be aware that if you really truly run that 15V LFP battery down to dead, it’s going to need to be replaced. There’s no charging it back up from dead without disassembling it … and that’s a Really Bad Idea.

 

[Bart404]

Just got my Uniden Radar Detector and was surprised to see the voltage from the "lighter" outlet in the center console read 13.6V.

 

[hgmichna]

Can that be confirmed? I have not measured. This would be a good solution. It would mean, however, that Tesla has installed some voltage reduction circuitry.

 

[Bart404]

Can that be confirmed? I have not measured. This would be a good solution. It would mean, however, that Tesla has installed some voltage reduction circuitry.

I just went out to check again. Uniden read 13.5V. Multimeter read 15.55V. Maybe the Uniden plug has a voltage limiter built in?

 

[hgmichna]

I tend to believe the > 15 V measurement.

By the way, I tested my 12 V tire pump, and it works on the higher voltage. Seems to pump a little faster.

 

[everydaychris]

agreed with the X i cant use the tire inflator so I got a battery powered one with the Y with my old 12v battery no issues

 

[hgmichna]

A little warning as to built-in-battery-powered air pumps—you will likely find yourself in a situation sooner or later when the little battery is empty, so you cannot pump. Recharging it takes far too long for most practical purposes.

This is why I recommend one that can be powered by the cigarette lighter socket.

 

[Tonedog77]

took a long trip with our MYP 22 with our iceco cooler worked perfectly, most well made devices have proper chips on the inside to adjust voltage

 

[soapinmouth]

I attached a small battery on the inside of the jump wire cover on the bumper and just leave it there permanently. If the 16v is dead, I can remove the cover, connect the battery to the cables to open the frunk.

View attachment 959146

Where did you find a 16v battery small enough to fit in here? Mind sharing?

 

[carlrbrugger]

Where did you find a 16v battery small enough to fit in here? Mind sharing?

An A23 battery will open the frunk.

 

[AudubonB]

I’ve never seen 16v out of my outlets. My cooler reads 15.2v resting from the rear plug and 14.5 when running, which draws 45w.

Multimeter question: how do you get a voltage reading when an object is running…or does your cooler itself provide a display?

 

[Mike728]

Multimeter question: how do you get a voltage reading when an object is running…or does your cooler itself provide a display?

You could always just get something like this:

 

[dmurphy]

Multimeter question: how do you get a voltage reading when an object is running…or does your cooler itself provide a display?

Not sure about his, but my 12V cooler does have a voltage display, yeah. I tried using a 12V extension cable in my Classic X with it and had just enough voltage drop for it to cut out occasionally.

Another advantage of the newer architecture.