12 Volts DC - Available in cabin?

[M0unt41nm4n]

So, there are no breakers and just one fuse (maybe 2) in the Cybrertruck AFAIK. Tesla doesn't use them, the vehicle's computer measure power on each circuit and will disable a circuit if the draw is too much. And this doesn't mean "too much" for the wire, it's what the computer things is too much for the devices on the circuit.

2 things:

1 - There is a fuse/breaker - call it the computer, a physical fuse, or a breaker switch. Something shuts down the power when there is too much current draw. We can call it all a fuse/breaker.

2 - The physical attributes of the wire. 16-18 gauge is about 10 amps before the wire starts to get hot. If there is no "fuse" (as defined above) to shut it down, the wire can heat enough to become damaged or start a fire. This is what fuses really are for.

So even if it works today, when everything on the circuit ramps up to full power, and there's more on the circuit than expected, the circuit may get shut down.

There is no way this is gonna happen with 400ma. I would be in shock if Tesla manufactured the draw on a 12v line to come to near its buck limit and that 400ma would take it over the top. That would be really stupid because amp draws are not necessarily stable. They move based on lots of factors including temperature, environment, initial power up load, etc. Anyone who thinks 400ma will exceed the rating and shut it down is smoking something stronger than is legal in the great state of Colorado. I am sure 400ma is within its wiggle limits by a long shot. If we are talking a 10A, draw, then maaaaayyyybeeeee.

Look... it's already been proven in this thread it works. Nothing got shut down. It's wayyy within the limits. So why are folks even arguing about this?

Sponsored

 

[Woodrick]

2 things:

1 - There is a fuse/breaker - call it the computer, a physical fuse, or a breaker switch. Something shuts down the power when there is too much current draw. We can call it all a fuse/breaker.

2 - The physical attributes of the wire. 16-18 gauge is about 10 amps before the wire starts to get hot. If there is no "fuse" (as defined above) to shut it down, the wire can heat enough to become damaged or start a fire. This is what fuses really are for.



There is no way this is gonna happen with 400ma. I would be in shock if Tesla manufactured the draw on a 12v line to come to near its buck limit and that 400ma would take it over the top. That would be really stupid because amp draws are not necessarily stable. They move based on lots of factors including temperature, environment, initial power up load, etc. Anyone who thinks 400ma will exceed the rating and shut it down is smoking something stronger than is legal in the great state of Colorado. I am sure 400ma is within its wiggle limits by a long shot. If we are talking a 10A, draw, then maaaaayyyybeeeee.

Look... it's already been proven in this thread it works. Nothing got shut down. It's wayyy within the limits. So why are folks even arguing about this?

No, It's not a fuse nor a breaker. I believe that it is a MOSFET that they use to control the power. Fuse or breakers require someone to replace or turn back on. That's not the case with the Tesla. In the cars, it monitors the 12V adapter that is in the car and will turn it off if overloaded and even keep it off until it sees the load removed.

But again, it's s 48V system, not 12V.
Maybe there is some Tesla provided 12V for the trailer connector, but odds are that if current draw is detected on it, it will put the car in tow mode.

Tesla is a different world, the rules are different. And the 48V system is radically new and does essentially power everything in the truck. Sure, internal to systems the voltage is changed, computers chips generally run below 5V, but the computer boards have 48V running to them.
The rules have changed!

 

[M0unt41nm4n]

No, It's not a fuse nor a breaker. I believe that it is a MOSFET that they use to control the power. Fuse or breakers require someone to replace or turn back on. That's not the case with the Tesla. In the cars, it monitors the 12V adapter that is in the car and will turn it off if overloaded and even keep it off until it sees the load removed.

I really hope it's not fully computer or MOFSET controlled (either way, I still call it a fuse/breaker... maybe lets call it an automatic fuse/breaker). The reason is if you get a bridge on it, it could quickly start a car fire. I hope there is a physical cutoff somewhere to prevent it. For my WARN winch, I installed the optional solenoid close to the battery for this very reason... get in an accident and those 4 gage wires will light the truck up like a Christmas tree. I don't know anything about Tesla vehicles, but for safety sake, I really hope that it has at least one main breaker near the battery for an accident causing a short.

 

[Woodrick]

I really hope it's not fully computer or MOFSET controlled (either way, I still call it a fuse/breaker... maybe lets call it an automatic fuse/breaker). The reason is if you get a bridge on it, it could quickly start a car fire. I hope there is a physical cutoff somewhere to prevent it. For my WARN winch, I installed the optional solenoid close to the battery for this very reason... get in an accident and those 4 gage wires will light the truck up like a Christmas tree. I don't know anything about Tesla vehicles, but for safety sake, I really hope that it has at least one main breaker near the battery for an accident causing a short.

It absolutely is.

The only fuses are the main battery stupidly huge ones and reportedly possibly on in the 12V trailer circuit, although this is probably secondary to the computer.

Not sure why you think you think that a bridge (diode full or half-wave bridge) would be a problem. If it see too much current, it just shuts it down.

That's the way that the Model 3 and Model Y have done it for years.

 

[M0unt41nm4n]

Not sure why you think you think that a bridge (diode full or half-wave bridge) would be a problem. If it see too much current, it just shuts it down.

Bridge meaning bad... not blown. Transistors and diodes can also fail by letting all current through like a short.

 

[Woodrick]

Bridge meaning bad... not blown. Transistors and diodes can also fail by letting all current through like a short.

It doesn't seem to have been a problem so far. That's how a lot of electronic high-power switches are today. How do you think that the power to the motors is controlled?

 

[M0unt41nm4n]

It doesn't seem to have been a problem so far. That's how a lot of electronic high-power switches are today. How do you think that the power to the motors is controlled?

Mofset failures:

https://www.powerelectronictips.com/how-and-when-mosfets-blow-up/

Does it happen in the Tesla? I have no idea. Maybe they have back ups and redundancy to a degree. If the power to the motor is controlled by MOFSET, then clearly it's a high voltage/current MOFSET and would take some nice current to burn it out (which it eventually would burn up acting as its own fuse - but the heat of it happening could cause a fire depending on how its encapsulated or not).

Back on track to the thread... 400ma ain't gonna blow it . Period.

 

[M0unt41nm4n]

Well lookey here

All about Tesla's "fuses":

https://teslatap.com/articles/fuses-and-current-protection/

Isn't this interesting? ?

Best part of it:

For example, we were doing some testing with always-on power from the drive control buttons on a 2022 Model S (the hidden drive buttons below the dual wireless phone chargers). With it powering a 400 mA dashcam, it worked fine.

 

[Woodrick]

Well lookey here

All about Tesla's "fuses":

https://teslatap.com/articles/fuses-and-current-protection/

Isn't this interesting? ?

Best part of it:

what components comprise the "electronic fuses" in a Tesla? - Page 1 (eevblog.com) as you read, MOSFETs.

But you seem to have missed the rest of the story. The translation is that on a specific circuit, 400mA may be okay, but just a little more could be deadly. Whatever 48V circuit that you find to downconvert to 12V may balk at the 100mA (when translated to 48V). They just happened to find a number that didn't upset this particular circuit.

We tried to add a larger 1.5 amp load for another accessory, or about 2 amps total, and it immediately “blew”. At this point the message appeared:

We removed all of our loads, but after 24 hours it did not clear. We also tried a hard reset and Powering down the car, but neither of these cleared the fault and restored power to this circuit. It was not a critical area, and I could otherwise use the car normally. After a software update about 10 days later, the eFuse reset. We don’t know if all eFuses reset after a software update, so a service appointment may be necessary. To be fair, these are not areas that Tesla recommends attaching accessories.

You may be able to get a USB-C converter to give you what you want.

 

[Woodrick]

Mofset failures:

https://www.powerelectronictips.com/how-and-when-mosfets-blow-up/

Does it happen in the Tesla? I have no idea. Maybe they have back ups and redundancy to a degree. If the power to the motor is controlled by MOFSET, then clearly it's a high voltage/current MOFSET and would take some nice current to burn it out (which it eventually would burn up acting as its own fuse - but the heat of it happening could cause a fire depending on how its encapsulated or not).

Back on track to the thread... 400ma ain't gonna blow it . Period.

And BTW, nothing blows. If the current utilization goes above what Tesla has programmed the computer to accept, it will shut it down. And as you can see from the article you posted later; different circuits may have different criteria for restarts.

 

[M0unt41nm4n]

what components comprise the "electronic fuses" in a Tesla? - Page 1 (eevblog.com) as you read, MOSFETs.

But you seem to have missed the rest of the story. The translation is that on a specific circuit, 400mA may be okay, but just a little more could be deadly. Whatever 48V circuit that you find to downconvert to 12V may balk at the 100mA (when translated to 48V). They just happened to find a number that didn't upset this particular circuit.




You may be able to get a USB-C converter to give you what you want.

... *everything* is a freaking argument on these forums... unbelievable. I didn't miss shit.

@Woodrick WHAT was the main issue? Can it drive 400 freaking milliamps without blowing the "fuse"? It most certainly can. Its within spec. Period. A little more would not be deadly. The electric fuse would blow... and it may allow you to reset, or it may not. Based on TeslaTap link I showed you, it will most likely allow a reset. Unplug the freaking radar detector and you are good. Based on TeslaTap, its allows 400ma. Based on users in this thread testing it out, the CT most certainly allows 400ma... hey IT WORKS! ?Weeee!

Please LOOK at the TeslaTap link... they have the entire breakdown of the e-fuse and how it works. They also have the physical fuses that you claimed they didn't have...also known as a PyroFuse, Inverter Fuse, and HV Pack Fuses.

I mean... WTF?... What in the Good Lord's name are you arguing about other than the sake of just being a troll and arguing about BS? You completely missed the point here...

To quote one of my favorite members here, @CyberGus, before he says it... "Y'all need Jesus"

 

[ideaXfactory]

Looks like a pretty good idea, but still not sure which of the two reds he used... It almost seems that If Tesla wanted the future option to put in a video mirror they would likely use that same power location.

 

[Gigahorse]

I mounted it using a double sided mount that I typically use on all of my vehicles because it is very minimalistic. I am looking at this as a permanent mounting location as it does not take windshield real estate and did not have to poke any holes for wiring as I am using rear view mirror door.

Long story short after testing a few leads I found this has Switched 12V power that turns off when truck goes to light sleep. It seems to power a small fan and possibly the temp/humidity sensor there.

This is just for information purposes, I reccomend you do proper research before wiring anything up!

Killer info to have, thanks so much for sharing.
This will enable those of us who use trailers to mount a digital rear view mirror that should have been shipped with the truck. GREAT info thanks!

 

[Gigahorse]

Have you found any 48V wires in there? If yes, a cheap bulk converter can do a job. I will do the same when receive my CB for Uniden R8.

You think the bulk converter will fit up there?

 

[gaubong053]

You think the bulk converter will fit up there?

I don’t have CT yet so not sure. There are many mini bulk converters with size as small as sd card.

Sponsored