Outside temperature accuracy

On another car I had the repair manual mentioned that type of delay and also said it had an extra delay when you first started the car because of the temperature rise in the grill area when the car was parked.

 

I have been very happy with the accuracy of mine so far. It virtually matches those displays on shops and also matches my home temp as I drive out

 

We don't have big temperature swing in Singapore so I didn't pay attention to the difference in OAT. After all these reports, I took my digital thermometer along to measure the actual outside temp. I've also setup the SGII to measure OAT and Cabin Room Temp. All temp in °C (°F). I took readings in the beginning of journey where the car has been parked for more than 8 hrs and another at the end of journey. Journey1 is evening and Journey2 is morning.

	Column 1
0	[TH]Method[/TH][TH]Start1[/TH][TH]End1[/TH][TH]Start2[/TH][TH]End2[/TH][TH]Start3[/TH][TH]End3[/TH][TH]Start4[/TH][TH]End4[/TH]
1	[TR][TD]Digital Thermometer[/TD][TD]31 (87.8)[/TD][TD]31 (87.8)[/TD][TD]29 (84.2)[/TD][TD]30 (86)[/TD][TD]30 (86)[/TD][TD]31 (87.8)[/TD][TD]29 (84.2)[/TD][TD]30 (86)[/TD][/TR]
2	[TR][TD]MFD OAT[/TD][TD]29 (84.2)[/TD][TD]26 (78.8)[/TD][TD]27 (80.6)[/TD][TD]27 (80.6)[/TD][TD]29 (84.2)[/TD][TD]26 (78.8)[/TD][TD]26 (78.8)[/TD][TD]26 (78.8)[/TD][/TR]
3	[TR][TD]SGII OAT[/TD][TD]29.9 (85.8)[/TD][TD]27.1 (80.8)[/TD][TD]27.2 (81)[/TD][TD]27.8 (82)[/TD][TD]29.5 (85.1)[/TD][TD]26.4 (79.5)[/TD][TD]26.7 (80)[/TD][TD]26.7 (80)[/TD][/TR]
4	[TR][TD]SGII Rm Temp[/TD][TD]30.2 (86.4)[/TD][TD]31.7 (89.1)[/TD][TD]27.4 (81.3)[/TD][TD]30.7 (87.3)[/TD][TD]30 (86)[/TD][TD]31.5 (88.7)[/TD][TD]26.7 (80)[/TD][TD]30 (86)[/TD][/TR]

My OAT seems to read 2°C lower when parked and 3°C ~ 5°C when moving. The SGII OAT has an additional decimal point so the difference is slightly smaller. I don't use A/C so the Rm temp is pretty close to outside temp.

Vincent

 

I think we can call this significant delay theory confirmed. Today on the drive to work it climbed from 26°C in the cool of my underground car park to 28°C when I shut down at work less than 15 minutes later. Actual outside temperature from two nearby official weather stations is 43°C. Only 109°F.

Air con worked fine again.

 

same here. delay theory that is, not 109 degrees.

 

Hottest day ever recorded in the Sydney CBD was 113.5°F. We're waiting to see if that record will be broken today. Peak so far is 113.4°F.

 

wow! i've never seen over 105 in my life.

 

I've played around with Techstream and there is 1 customize option that can be adjusted to match the display ambient temperature against the OAT.



The default is Normal and I adjusted it to +1C. Now, the display ambient temperature reads 1°C lower when parked and 2°C ~ 4°C when moving. There is no +2C so this is the closest I can adjust. Anyway, it is no big deal to me since the display ambient temperature only affects the AUTO function of A/C which I seldom use.

Vincent

​

 

Okay so I can again confirm that the outside temperature display drops MUCH faster than it will go up.

We did indeed set a new record, hitting 45.8°C (114.4°F). Locally, it was 36.3 when I left work and a cool change moved through while I was at the shops, dropping to 27.3 (81.1°F) around the time of my final leg home. Although that was the official temperature at a nearby location, by this stage there were howling 20-30 knot winds and pouring rain and the car was actually showing 24. It's been a very odd day of very location-sensitive weather, so the discrepancy doesn't surprise me - just interesting that it's so willing to drop quickly on the display when it will not climb the same way.

 

My outside temp is also off significantly. I noticed the other day when I was freezing my nice person off and the display was reading 40F.

After careful checking under various conditions and against a bank's display, my Ford Escape, and a thermometer, I've determined the C's sensor is constantly reading 7F too high.

 

It's cold here! Mine seems to be in the ballpark

 

yep, i know it was below freezing here in Indy, in fact we were in the single digits but LePrePre was only reading 19 degrees F.

 

My 2008 Prius is missing the outdoor temp sensor. Anyone know the PN and supply source?

 

My 2013 Prius Four seems to be greatly affected by sunlight. It' says if the outside temp sensor is under the engine hood somewhere.

Stupid ipad changed my comment. I meant, "It's as if the outside temp sensor is under the engine hood somewhere."

 

It's maybe 1 degree higher than Ultragauge on mine but I don't count any of the temperature readings if the car sits in the sun all day.