Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Overloaded cigarette lighter port with power inverter, no fuse to replace

arghx7

Member
Aug 6, 2019
511
516
Michigan
2019 Model 3 LR AWD, May build date.

Today I plugged in a power inverter into the cigarette lighter port in the center console (only checked the owner's manual later and saw that's supposed to be not permitted). I activated the inverter by pressing the button and it lit up. I plugged in a baby bottle warmer (for my kid, going on a road trip tomorrow). I turned the knob on the warmer and as it got above 50% the power cut off. I heard a clicking sound like a circuit breaker going.

Now I can't get the cigarette lighter to output any juice. My Multimeter shows 0 volts across it. Battery voltage (vehicle parked, plugged into mobile charger at 120v) across the 12V is 13.5 volts. The USB A ports near the infotainment screen work fine and my iPhone will charge when plugged into it. I tried a hard restart by going into safety & security, selecting it, then waiting 3 minutes. No luck.

I searched the owner's manual and found nothing. Google searches tell me there is no fuse box like a conventional car. I even have access to a service manual and I don't see anything in there (or maybe I just missed it) about this. I'm assuming there's no damage to anything considering the power inverter still works fine when I plug it into another car and the USB-A ports are working. Is there a way to reset the cigarette lighter power port without putting in a service ticket? Maybe there is some kind of timer before it turns back on? I'm going on a road trip with the car tomorrow so a service ticket is not an option.

Anyone ever overloaded the cigarette lighter? Do you have any advice?


The inverter:

https://www.amazon.com/gp/product/B07F8J7X6K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 

DopeGhoti

Active Member
Aug 28, 2019
1,237
1,394
Phoenix, AZ
Apparently according to Tesla (via reasearsh from Abstract Ocean), the best way to force a reset of the "fuses" if they don't self-reset in 90 minutes or so is to disconnect the 12V battery for a few seconds.
 

arghx7

Member
Aug 6, 2019
511
516
Michigan
so just pop the Frunk, remove the trim piece, remove the negative terminal for a few seconds, and then put it back on? Is there anything else involved in that?
 

KenC

Active Member
Sep 4, 2018
3,706
3,363
Maine
I would have guessed a hard reset would do the trick, but guess not. I'd just leave it for a few hours, like others have suggested. It should reset by itself.
 

arghx7

Member
Aug 6, 2019
511
516
Michigan
So I checked about two hours later and the cigarette lighter is still putting out 0 volts. It's a 10mm nut to remove the negative battery terminal, but with my luck something will go wrong if I do it now and I'll have to call service. So I'll deal with it when I get back from my trip. I don't really need the cigarette lighter port, it was just a "nice to have" for a working power inverter.
 

EmOne

Member
Mar 28, 2020
218
161
Chicago
So I checked about two hours later and the cigarette lighter is still putting out 0 volts. It's a 10mm nut to remove the negative battery terminal, but with my luck something will go wrong if I do it now and I'll have to call service. So I'll deal with it when I get back from my trip. I don't really need the cigarette lighter port, it was just a "nice to have" for a working power inverter.
I wouldn't want to go on a trip without a means to power a pump for the tires!
 

Brock-WI

Member
Aug 4, 2020
76
59
Green Bay, WI
When I have had this happen I did the "tesla two thumbs salute" Basically restarting the computer by pressing and holding both thumbwheels until the screen shuts off and restarts. Not sure why this worked but I have done it more than once to reset the 12v outlet.
 
  • Like
Reactions: insider

KenC

Active Member
Sep 4, 2018
3,706
3,363
Maine
I wouldn't want to go on a trip without a means to power a pump for the tires!
I keep telling myself the most foolproof pump is one of those double-piston floor pumps that you use with your foot. That way you don't have to worry about the fuse, etc. Of course, I'm too lazy to buy one, and they're quite cheap!

Now that I think about it, maybe I'll stick one of those tiny hand pumps for my bike in my car, for emergency use.
 

Timbo2

Member
Jun 8, 2019
201
158
USA
I keep telling myself the most foolproof pump is one of those double-piston floor pumps that you use with your foot. That way you don't have to worry about the fuse, etc. Of course, I'm too lazy to buy one, and they're quite cheap!

Now that I think about it, maybe I'll stick one of those tiny hand pumps for my bike in my car, for emergency use.

This is my tool bag for my 12V compressor in case of outlet issues.

https://www.amazon.com/gp/product/B072MZM74S/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 
  • Like
Reactions: KenC

dmurphy

Buster: 11/25/14 - 6/20/21. So sorely missed.
Supporting Member
Dec 7, 2018
3,778
5,127
New Jersey - Morris County
The Model 3 doesn't have traditional fuses; it uses solid state "E-Fuses".

The click you heard was likely from behind the front, left hand side A-Pillar. That's where the "VCLEFT" (Vehicle Controller, Left) resides. VCLEFT is responsible for the 12V power sockets among many other functions.

A dual-scroll-wheel reset will likely restore power to the 12V sockets.

Specifically, Tesla's firmware does not restore power immediately. The eFuse controlling the 12V outlets latches off until the microcontroller is reset; this can be done either via a timer (i.e. wait a few hours) - or you should be able to force a microcontroller reset by doing a hold-down-both-scroll-wheels-reset.

If the dual-scroll-wheel reset doesn't do the trick, you can go to the next step and cycle the entire car via the Service menu.

Either way you'll be fine - and I'd try it before going on the trip. Won't hurt anything - this is the e-Fuse that's tripped and it's functioning exactly as designed.
 
  • Informative
Reactions: zhu-

neurocutie

Member
Dec 2, 2019
359
170
upstate ny
2019 Model 3 LR AWD, May build date.

Today I plugged in a power inverter into the cigarette lighter port in the center console (only checked the owner's manual later and saw that's supposed to be not permitted). I activated the inverter by pressing the button and it lit up. I plugged in a baby bottle warmer (for my kid, going on a road trip tomorrow). I turned the knob on the warmer and as it got above 50% the power cut off. I heard a clicking sound like a circuit breaker going.

The inverter:

https://www.amazon.com/gp/product/B07F8J7X6K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
What's the power draw of the baby bottle warmer?

The inverter looks like it would be drawing well over 15A max... which is a bit much for that port. If the warmer is a "dumb" warmer, remember that most heating elements have very low resistance when cold and will draw a lot more current til it warms up. So its rating may belie its cold startup power draw.

Also again depending on the design of the warmer, 50% may not mean 50% max power draw but rather ~50% temperature but reaching it using 100% current draw in a on/off (pulsed) fashion, like a thermostat.

Since apparently the warmer is designed for 120VAC usage, it expected to be able to draw as much as 15A 120VAC to operate, even if the time-averaged power rating is lower (than say 1500watts). For example, even if it is rated for, say 150watts, it could still transiently draw, say 300-500watts, which at 12V could be well over 20A.

There are travel baby bottle warmers designed for 12V auto usage, which are likely to yield more compatible results.
 
Last edited:
  • Like
Reactions: comraddan

Products we're discussing on TMC...

About Us

Formed in 2006, Tesla Motors Club (TMC) was the first independent online Tesla community. Today it remains the largest and most dynamic community of Tesla enthusiasts. Learn more.

Do you value your experience at TMC? Consider becoming a Supporting Member of Tesla Motors Club. As a thank you for your contribution, you'll get nearly no ads in the Community and Groups sections. Additional perks are available depending on the level of contribution. Please visit the Account Upgrades page for more details.


SUPPORT TMC
Top