# Forums

The internal temperature settings support 1/2 degree C increments (equal to .9F), but the external temperature is only reported in whole degrees C. Pretty trivial, I know, but probably trivial to fix as well (presumably just a display issue), and worthwhile as the international market grows.

:’(

andy.connor.e | 2019年11月7日

I dont understand. Do you want internal temp settings to be in 1 deg C increments?

derotam | 2019年11月7日

@andy.connor.e: no they want outside temp to be in 1/2 degree increments.

andy.connor.e | 2019年11月7日

ugh!

bp | 2019年11月7日

Yeah, outside temp. There is a big difference between 0C and 1C, in particular, for driving conditions.

I expect there would be plenty of objections if the external temperature only displayed in even-degrees Fahrenheit.

andy.connor.e | 2019年11月7日

time to convert the world to fahrenheit.

jimglas | 2019年11月7日

the horror!

booshtukka | 2019年11月7日

Pretty much the whole world uses Celsius, since it is a sane measurement of temperature. It's only the US and a handful of other small countries that use Fahrenheit.

booshtukka | 2019年11月7日

(FYI that's about 5% of human beings).

hokiegir1 | 2019年11月7日

@bp - "I expect there would be plenty of objections if the external temperature only displayed in even-degrees Fahrenheit."

It does. So does the internal. I can set the internal temp to 64 or 65 F -- but not 64.5F. External is also rounded increments only.

derotam | 2019年11月7日

@booshtukka: Quantity doesn't always equal quality... :)

bp | 2019年11月7日

@hokiegir1: you misunderstand - not “even” as in “whole”, “even” as in “even numbers only”.

Every degree centigrade is roughly equal to 2 degrees Fahrenheit. So a 1/2 degree C is roughly equivalent to 1 degree Fahrenheit. So if you display the exterior temperature in whole centigrade only, it would be analogous to only displaying Fahrenheit in even (or odd) degrees, e.g. 2, 4, 6, 8 - skipping by 2. That would bug you, I’m sure. ;)

My point is that the external thermometer is accurate to the 1 degree Fahrenheit (and 1/2 degree C), so it should display in 1/2 degree centigrade precision.

hokiegir1 | 2019年11月7日

@bp - Oohhh. Ok. I did misunderstand that one. Let's just blame lack of coffee this morning. :) And I only like even numbers for my settings (I do 64 or 66 ...I skip 65), but it would still be annoying, so I do get that.

Atoms | 2019年11月7日

Agreed

bp | 2019年11月7日

Especially if it was showing the outside temp only as 32F or 34F, but never 33F. That’s an important distinction for road conditions and battery status when parked...

slingshot18 | 2019年11月7日

You’re equating display to accuracy. Has that been proven? I’d guess both are off more than you’d guess.

lbowroom | 2019年11月7日

If only the outside temperature gauge was accurate to anywhere near 1 degree in either F or C

lbowroom | 2019年11月7日

water freezes at 32F but all cold weather warnings I've seen trigger at 37F. +/-1 C degree in readout makes no real world difference in how you should live your life.

bp | 2019年11月7日

@slingshot18: you’re right that I’m assuming it’s accurate to within 1°F; it may not be. But that’s actually irrelevant here, because the distinction I’m making isn’t about the accuracy of the external thermometer, it’s about the precision of reporting it: for No Good Reason, the external temperature displayed is less precise when set to C than when set to F, by the equivalent of nearly 1°F. The actual reported temperature will be equally accurate or inaccurate irrespective of the units, assuming equal precision in reporting it.

For example, displaying 5C should be nearly as accurate as displaying 41F, and displaying 33F should be nearly as accurate as displaying 0.5C.

lbowroom | 2019年11月7日

What's the value of displaying significant digits beyond the level of it's accuracy?

dmastro | 2019年11月7日

Throwing my hat in the ring in support of the Kelvin scale.

lbowroom | 2019年11月7日

To answer your question above, I would have no problem with the display reading in even F units for external temp. 2 4 6 8 10 etc

lbowroom | 2019年11月7日

When I lived in Europe, not once did someone quote me temperature in 1/2 degree C

CharleyBC | 2019年11月7日

"Throwing my hat in the ring in support of the Kelvin scale."

I like it! Right now it's 297K outside here in Sacramento. I think we broke 300 earlier this afternoon.

bp | 2019年11月7日

@lbowroom: humorously, my pointing out the inconsistency seems to bother some people more than the inconsistency itself bothers me. ;) But for the sake of argument: if the outside temperature is changing ~1°F every 5 minutes of driving, the centigrade display is going to take 10 minutes to reflect it. Again, this isn’t an issue of accuracy, it’s an issue of precision (which is more relevant with relative measurements than with absolute ones).

As I said in the original post, this is “pretty trivial”. But the inconsistency was noticeable to me coming from Audi.

Cheers,

kaffine | 2019年11月7日

No there really isn't a big difference in driving conditions between 0º and 1º C, As you are looking at air temp not surface temp which may be lower or higher. The cars I have driven that have alerts for icy conditions all have the warning come on well above freezing.

You are right though I would be annoyed if they only reported even numbers in ºF I am way to odd to be using even numbers. Now if they only reported odd numbers skipping the even I would be fine.

andy.connor.e | 2019年11月8日

There seems to be a lack of willing to think.

derotam | 2019年11月8日

Temperatures are to at least 1/10 of a degree as per CANbus data.

RichardKJ | 2019年11月8日

@lbowroom
"When I lived in Europe, not once did someone quote me temperature in 1/2 degree C"

When I've been in hotel rooms in Celsius-land the digital thermostat settings are almost always in increments of 0.5º C.

andy.connor.e | 2019年11月8日

Ya well the outside temperature thermometer in the car is measuring current temperature and not controlling temperature.

gballant4570 | 2019年11月8日

Its just a matter of what you are used to. When I was a working man..... I spent about a decade working on international projects (thermal power generating station engineering and design) for which all metric measurements were used, including temperature and pressure. My conceptual thinking shifted as well, and I was in the habit of mentally converting US inputs to metric data in my head to give me a better intuitive understanding of it.

That decade ended more than a decade ago. Now I have gone back the other way. It's a little sad. However, the Fahrenheit temperature scale is a bit more granular than the Celsius scale. The best of both could be put together, which would result in smaller degrees or increments with zero set on the freezing point of H2O at sea level.

I would vote for that.

gballant4570 | 2019年11月8日

Not under the control of Tesla, of course.

walnotr | 2019年11月8日

Water freezes at 0 and boils at 200. Problem solved.

kevin_rf | 2019年11月8日

Walnotr, at what pressure?

lbowroom | 2019年11月8日

Richard. so is the tesla temp controller. I'm talking about outdoor temp readings as well as broadcast forecasts

lbowroom | 2019年11月8日

ever hear a weatherman say, 'The forecast high for the day is 21.5"

TeslaTap.com | 2019年11月8日

But think of all the power that's saved by not showing the extra temperature digit all the time! I'm sure Tesla has done extensive analysis to define the least amount of digits necessary to display and save miles of range.

For the humor-impaired, it doesn't actually take any additional power once the entire display is active.

Syed.Hosain | 2019年11月8日

@dmastro "Throwing my hat in the ring in support of the Kelvin scale."

ROFL. Heck, yeah!

People would still ask for 0.5 degree K increments though. :)

dmastro | 2019年11月8日

CharleyBC: Amazingly enough, it's 279 Kelvin right now in Sacramento too! And time to start my weekend.

kevin_rf | 2019年11月8日

This Kevin tried to avoid the scale. Numbers like dmastro is throwing around is why...

lbowroom | 2019年11月8日

Are you sure it’s not 279.5?

bp | 2019年11月8日

“Are you sure it’s not 279.5?“

Only way to find out is to go into settings, switch to Fahrenheit, do the math, and switch back. Piece of cake.

slingshot18 | 2019年11月8日

@bp There may be or may not be a “good reason” for it. Did you ask the programmer? We just don’t know. Maybe it was aesthetics.

kevin_rf | 2019年11月9日

I'm sure programmer just followed the specs that came out of committee...

Pg3ibew | 2019年11月9日

@walnotor, "Water freezes at 0 and boils at 200. Problem solved."
0 Freezing is Celsius. Where does 200 come in to play?

walnotr | 2019年11月9日

@Pg3ibew - It is just a hypothetical recalibration to adjust the scale making math easier and get rid of the 1/2 degree conversion error. Presented tongue in cheek but also trying to point out how arbitrary “standards” can be.

Pg3ibew | 2019年11月9日

@walnotr, got ya. As I am reading between this thread and the VW charging thread, I notice the mathematical calculations being tossed about. So I went and grabbed my Abicus, protractor, chalk board and slide rule to try and keep up. Lmao

walnotr | 2019年11月9日

@Pg3ibew - Setting 0 degrees to the freezing point of salt water made sense in the maritime world when concerns of being ice bound can mean life or death. I can’t recall how 212 became the number for boiling water.

I gave my engineer son my slide rule. It’s probably in a landfill by now.

kevin_rf | 2019年11月9日

I thought salt water froze at 28.5 f

Pg3ibew | 2019年11月9日

@walnot. 100 degrees celcius is Boiling. I will now give the reason 212F is boiling.
The C to F math goes like this.
0 C X 9/5 + 32 = 32F Freezing point of water in Fahrenheit
100 C x 9/5 + 32 = 212 Boiling point of water in Fahrenheit

walnotr | 2019年11月9日

@Pg3ibew - those are the conversion formulas, I think the two scales were developed independently based on different real world observations. Time for me to fire up the google machine.