Thermometer Converts from Celsius?
#1
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The temperature around here has been fluctuating around 32 degrees last couple of days and I was noticing that the outside temperature read-out jumps from 32 to 34 or from 32 to 30. At first I thought that it was only showing even number degrees.
At colder temperatures I noticed it indicates in odd numbers. This makes me come to a conclusion that the temperature must be sent to the computer in Celsius and then converted to Fahrenheit.
I have a Japanese built Camry. Wondering if the US built are the same way. Not that it affects my life in the least little bit, but just curious of this little observation. I don’t recall my 2004 Camry having the same temperature behavior.
At colder temperatures I noticed it indicates in odd numbers. This makes me come to a conclusion that the temperature must be sent to the computer in Celsius and then converted to Fahrenheit.
I have a Japanese built Camry. Wondering if the US built are the same way. Not that it affects my life in the least little bit, but just curious of this little observation. I don’t recall my 2004 Camry having the same temperature behavior.
#2
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I haven't payed attention to this. I typically have my MFD set at the MPG screen so that's why I haven't noticed. I'll have to switch it over to the temp screen to check it out. I also have a Japan built TCH.
#3
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skata — All the internal car data is measured and transmitted in metric units (liters, kilometers, etc.). That's probably been true of all the car companies for decades now. That's one reason why the bolts have been metric for some time now. The CAN bus carries this metric data, which is being converted to US units for the US market. The Canadian TCHs are metric, and so read temperatures in degrees Celsius. You're probably right that the jumps seen in your degrees Fahrenheit readout is due to the conversion from Celsius to Fahrenheit — nearly two (actually 9/5) degrees F to each degree C.
Stan
Stan
#4
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Not that I want to highjack this thread, but has anyone noticed that the MFD thermometer readout seems to be always 2-4 degrees Fahrenheit higher than what's reported on the news? Looks like it may not be calibrated correctly, akin to the MPG and MPH readouts this forum has discussed in the past (i.e. MPG being off by 1-2% from manual calcs, MPH stating lower speeds than actual, etc).
This could be due to the thermometer being too close to the ICE (and measuring residual heat), but I've noticed this discrepancy even when the engine is "cold"...
FYI, for comparison purposes: my TCH is Japan-built, low(ish) VIN, US market (i.e. miles/Fahrenheit).
This could be due to the thermometer being too close to the ICE (and measuring residual heat), but I've noticed this discrepancy even when the engine is "cold"...
FYI, for comparison purposes: my TCH is Japan-built, low(ish) VIN, US market (i.e. miles/Fahrenheit).
#5
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Not that I want to highjack this thread, but has anyone noticed that the MFD thermometer readout seems to be always 2-4 degrees Fahrenheit higher than what's reported on the news? Looks like it may not be calibrated correctly, akin to the MPG and MPH readouts this forum has discussed in the past (i.e. MPG being off by 1-2% from manual calcs, MPH stating lower speeds than actual, etc).
This could be due to the thermometer being too close to the ICE (and measuring residual heat), but I've noticed this discrepancy even when the engine is "cold"...
FYI, for comparison purposes: my TCH is Japan-built, low(ish) VIN, US market (i.e. miles/Fahrenheit).
This could be due to the thermometer being too close to the ICE (and measuring residual heat), but I've noticed this discrepancy even when the engine is "cold"...
FYI, for comparison purposes: my TCH is Japan-built, low(ish) VIN, US market (i.e. miles/Fahrenheit).
#6
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I agree - my thermometer has seemed very accurate compared to the remote outdoor thermometer at my house.
#7
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I agree, I find the temp readout to be very accurate to local conditions. My Sienna has a temp display too that is also pretty accurate. On both vehicles I've always been impressed how well it seems to handle sitting in the sun. Although it will register a few degrees high at startup, it seems to find the right temp pretty quickly after 3 or 4 of driving.
#8
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Today, in the desert SW, it is a balmy 60ish degrees F. The TCH's thermometer changed several times from 59-61, and back to 59 over a 30-45 minute errand run around town, never displaying 60.
(Just more info for this thread.)
(Just more info for this thread.)
#9
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This is what I was indicating in the begining of this thread. I don't recall my 2004 Camry skipping digits.
#10
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More info: Over the last few days the temps here have varied from mid 40s F to just over 70. I have noted the temps that our TCH displays in that range and their C conversion on the left, and on the right, as if the thermometer was in fact reading in C, and converting to F for display purposes:
Converting from F to C:........................ Converting from C to F
F ....... C............................................... C............F ... rounded/will display as
43........6.11 ............................................6......42.8......43
45........7.22 ............................................7......45.........45
46........7.77 ............................................8......46.4......46
48........8.88 ............................................9......48.2......48
50........10 ..............................................10......50........50
52........11.11 .........................................11......51.8.....52
54........12.22 .........................................12.......53.6....54
55........12.77..........................................13......55.4.....55
57........13.88..........................................14......57.2.....57
59........15 ............................................. 15......59........59
61........16.11 ..........................................16....60.8.......61
63........17.22 ..........................................17....62.6........63
64........17.77.......................................... 18.....64.4.......64
66........18.88 ..........................................19......66.2......66
68........20 ..............................................20......68.........68
70........21.11 ..........................................21....69.8.......70
So..It in fact appears that skata is right, the info is collected in degrees C and converted to F and then rounded to the nearest whole digit!
Converting from F to C:........................ Converting from C to F
F ....... C............................................... C............F ... rounded/will display as
43........6.11 ............................................6......42.8......43
45........7.22 ............................................7......45.........45
46........7.77 ............................................8......46.4......46
48........8.88 ............................................9......48.2......48
50........10 ..............................................10......50........50
52........11.11 .........................................11......51.8.....52
54........12.22 .........................................12.......53.6....54
55........12.77..........................................13......55.4.....55
57........13.88..........................................14......57.2.....57
59........15 ............................................. 15......59........59
61........16.11 ..........................................16....60.8.......61
63........17.22 ..........................................17....62.6........63
64........17.77.......................................... 18.....64.4.......64
66........18.88 ..........................................19......66.2......66
68........20 ..............................................20......68.........68
70........21.11 ..........................................21....69.8.......70
So..It in fact appears that skata is right, the info is collected in degrees C and converted to F and then rounded to the nearest whole digit!
Last edited by jbollt; 03-04-2007 at 02:06 PM.