Why can't the car just STAY ON (and hack-workaround)

[gillmj24]

So one tire slowly loses air and I wanted to put a few pounds in.

My ryobi inflator has a pressure display but want to see how well it matches the Tesla TPMS.

SO of course it goes "car off" as soon as you put in park and get up off the driver seat occupancy sensor.

I'm sure someone discovered this but after I got out I put my laptop backpack on the brake pedal to turn the car back on and keep the tire psi displayed as I inflated. Kind of dangerous since it could slip and push the accelerator but it was in Park.

Are newer teslas the same? I hate when technology tries to outsmart you. I'm smart and I know what I want to do. Missing an "accessory" mode. Side note 2023 Bolt EUV is sort of the same but worse, you have to get in push the brake and the power button to have ANYTHING powered.

The leaf was the best here, it had a push the start button from anywhere including the passemger seat, without touching the brake to turn on a traditional Accessory mode.

 

[brkaus]

I have 1 2017 S and a 2018 3. Both will keep the power on for the accessory port for at least some amount of time as long as I keep the door ajar. Which, I generally do for the inflater cord. I believe you can also touch the screen after it goes back to power things up again.

 

[gillmj24]

For me it says "car off" on the instrument cluster even leaving the door ajar

 

[gillmj24]

If i want to check exterior lights, I want "CAR ON" As well

Been dealing with a wonky left headlight for a while.

 

[spsheridan]

So one tire slowly loses air and I wanted to put a few pounds in.

My ryobi inflator has a pressure display but want to see how well it matches the Tesla TPMS.

SO of course it goes "car off" as soon as you put in park and get up off the driver seat occupancy sensor.

The TPMS in newer Teslas requires some time driving the car for the TPMS readings to update - they don’t take static measurements. I don’t think you’ll be able to get an accurate TPMS reading as you inflate your tires while the car is in Park.

I thought this applied to all Teslas but maybe not as far back as 2015. Are you seeing TPMS readings change while the car is in Park?

 

[gillmj24]

The TPMS in newer Teslas requires some time driving the car for the TPMS readings to update - they don’t take static measurements. I don’t think you’ll be able to get an accurate TPMS reading as you inflate your tires while the car is in Park.

I thought this applied to all Teslas but maybe not as far back as 2015. Are you seeing TPMS readings change while the car is in Park?

I have a 2015 and once TPMS were on from having driven, it stayed on while I inflated at the end of my commute. Of course I had to keep a weight on the brake pedal to do this. I couldn't see it updating live of course, but I did verify at the end of my fill up that it did record the 4psi I added.

 

[spsheridan]

I have a 2015 and once TPMS were on from having driven, it stayed on while I inflated at the end of my commute. Of course I had to keep a weight on the brake pedal to do this. I couldn't see it updating live of course, but I did verify at the end of my fill up that it did record the 4psi I added.

That's interesting. Maybe Tesla removed static TPMS measurements as a cost-saving measure. I wonder what year they made that change.

 

[livesmith]

That's interesting. Maybe Tesla removed static TPMS measurements as a cost-saving measure. I wonder what year they made that change.

I've not static measurements in my 15' 85D (Well other than after coming to a stop with previously recorded measurements). To my knowledge this is to save the batteries in the TPMS sensors. They don't transmit until they're moving? (though my Autel unit can trigger them so maybe I'm mistaken)

 

[RedTesY]

Just use a good quality tire pressure gauge!

 

[DerbyDave]

Also, the App displays the last tire pressure with the car last running. As stated above the pressure will not change with the car stopped-- it is the last measurement while driving.

 

[livesmith]

Also, the App displays the last tire pressure with the car last running. As stated above the pressure will not change with the car stopped-- it is the last measurement while driving.

Which would be a warm tire pressure and generally you want to measure/add tires when cold. I.e. first thing in the morning before driving.

 

[gillmj24]

Just use a good quality tire pressure gauge!

Still needs to be calibrated to something, and a good check for the Tesla TPMS.

 

[gillmj24]

Which would be a warm tire pressure and generally you want to measure/add tires when cold. I.e. first thing in the morning before driving.

One tire gets 3-4 pounds low every few weeks. The delta is the same cold or warm.

 

[DerbyDave]

Which would be a warm tire pressure and generally you want to measure/add tires when cold. I.e. first thing in the morning before driving.

Yes, to check my guage, I fill to the pressure I want cold, and then drive about 1/4 mile to get the tire pressure from the car display when it first comes on. My tire guage is accurate.

 

[livesmith]

Still needs to be calibrated to something, and a good check for the Tesla TPMS.

Yeah, I'm finding it hard to tell which is most accurate between the gauge on my large air compressor, portable air compressor or Tesla TPMS... Close to 5PSI difference sometimes. And for some reason it seems like my left rear tire always reads 1psi lower than the others via the TPMS, even after wheel changes...

 

[gillmj24]

Next time I'll have my son keep his foot on the brake while I fill the tire and he'll film to see if it updates every PSI

 

[DerbyDave]

The battery in the tire pressure monitor would be soon completely discharged if the monitor would update stationary that often.

 

[gillmj24]

I've also wanted to keep the car ON while hooking up, testing, or downloading from my garmin dashcams. Have to do that sitting in the car so I can keep it from going OFF after the aforementioned timeout.

 

[DerbyDave]

Press on the brake every 10 minutes.

 

[WyoDude]

Kind of dangerous since it could slip and push the accelerator but it was in Park.

Dangerous?
I’d love to see the scenario in which your backpack splits apart, keeps some weight on the brake, while the other half flies up and hits the gear stake from above to push it down and then it all falls back to floor and moves all the weight to the accelerator and then your car is on the loose and out for blood…