outside temperature readings, how accurate are they?

Rick-sta · 25th August 2016, 13:54

How accurate is the outside temperature reading on our cars which is displayed on the ipk? Yesterday i was reading between 39-43oc through the hottest hours of the day, although the weather forecast stated around 32oc. My zt and my dads 75 both picked up the same temperature readings. It was very hot in essex yesterday, so hot that anyone just standing outside chatting was sweating! But surely it couldnt have been that hot?

Cheers

SCP440 · 25th August 2016, 14:14

The temperature you see on the weather forecast is measured in the shade, your sensor in the front bumper should be in the shade but heat from the car has some effect together with some heat soak through the skin of the bumper. At best it is a guide and if you have 2 cars within a degree or two I suspect that is the actual temperature.

BigAde · 25th August 2016, 14:18

With the car moving, the flow of air through the front bumper should keep it relatively accurate, although I suspect mine still reads a couple of degrees on the warm side. As soon as the car is stopped, the flow of air stops and the oven-effect will mean the air within the front bumper will warm up more than the outside air.

Ravinder · 25th August 2016, 14:46

Can it be rerouted elsewhere to give a more accurate reading?

SCP440 · 25th August 2016, 15:19

Quote:

Originally Posted by Ravinder

Can it be rerouted elsewhere to give a more accurate reading?

They put it there as that is the best place, anywhere rear of that and it could affected once the cooling fan cuts in or by the heat off the exhaust.

first-things-first · 25th August 2016, 17:23

Quite a few cars have temp sensors below one wing mirror. Might avoid engine heat soak.

bl52krz · 25th August 2016, 19:22

Quote:

Originally Posted by first-things-first

Quite a few cars have temp sensors below one wing mirror. Might avoid engine heat soak.

I would imagine that that is worse than where ours is located for obvious reasons.

Rick-sta · 25th August 2016, 22:00

thanks all

pretty much what I was thinking that they overread. My car had been sitting on the driveway all day so hadn't been driven yesterday, but turned the key to check the temp a few times, which is when I was getting 40 oc. Have always wondered if the temp would under read when on the motorway due to the air blowing onto the sensor

7T5 · 26th August 2016, 11:48

I joke with my wife that the temp displayed is the temp in Longbridge

25th August 2016, 13:54	#1
Rick-sta This is my second home MG ZT 2.0 CDTI+ in Typhoon, MG TF 135 in Typhoon & Rover 75 Connoisseur CDTI SE in Pearl Black Join Date: Oct 2012 Location: Norfolk Posts: 7,534 Thanks: 2,718 Thanked 2,827 Times in 1,462 Posts	outside temperature readings, how accurate are they? How accurate is the outside temperature reading on our cars which is displayed on the ipk? Yesterday i was reading between 39-43oc through the hottest hours of the day, although the weather forecast stated around 32oc. My zt and my dads 75 both picked up the same temperature readings. It was very hot in essex yesterday, so hot that anyone just standing outside chatting was sweating! But surely it couldnt have been that hot? Cheers __________________ How to retrofit Cruise Control on a diesel with no OEM wiring in place: Link How to retrofit heated electric memory seats with no OEM wiring in place: Link How to operate FBH and ATC via text Link How to restore cloudy projector headlights Link

25th August 2016, 14:46	#4
Ravinder This is my second home Rover 75 saloon x2, Rover 75 Tourer x2, Rover 220 Coupe Turbo Join Date: Aug 2010 Location: Kirkcaldy, Fife Posts: 9,036 Thanks: 2,278 Thanked 2,852 Times in 1,718 Posts	Can it be rerouted elsewhere to give a more accurate reading? __________________ Wanted - Indian bride. Cash waiting. (All sorted - bargain) First name and forum name: Ravinder Rover 75 2.0 CDT Connoisseur SE 116 (160 remap) Royal Blue (JFM) This vehicle was the 50,481st 75 to run off the production line, out of 112,381 This vehicle was the 2,238th 75 CDT Connoisseur SE to be made out of 3,775 This vehicle was the 5,002nd 75 in Royal Blue (code: JFM) to be made out of 14,420 Royal Blue 75s

25th August 2016, 22:00	#8
Rick-sta This is my second home MG ZT 2.0 CDTI+ in Typhoon, MG TF 135 in Typhoon & Rover 75 Connoisseur CDTI SE in Pearl Black Join Date: Oct 2012 Location: Norfolk Posts: 7,534 Thanks: 2,718 Thanked 2,827 Times in 1,462 Posts	thanks all pretty much what I was thinking that they overread. My car had been sitting on the driveway all day so hadn't been driven yesterday, but turned the key to check the temp a few times, which is when I was getting 40 oc. Have always wondered if the temp would under read when on the motorway due to the air blowing onto the sensor __________________ How to retrofit Cruise Control on a diesel with no OEM wiring in place: Link How to retrofit heated electric memory seats with no OEM wiring in place: Link How to operate FBH and ATC via text Link How to restore cloudy projector headlights Link

25th August 2016, 14:14	#2
SCP440 I really should get out more....... MG ZT-T 260 Join Date: Feb 2016 Location: Witney Posts: 2,504 Thanks: 6 Thanked 910 Times in 571 Posts	The temperature you see on the weather forecast is measured in the shade, your sensor in the front bumper should be in the shade but heat from the car has some effect together with some heat soak through the skin of the bumper. At best it is a guide and if you have 2 cars within a degree or two I suspect that is the actual temperature.

25th August 2016, 14:18	#3
BigAde Posted a thing or two MG ZT-T+ 135 CDTi Join Date: Oct 2012 Location: Sussex Posts: 1,502 Thanks: 511 Thanked 224 Times in 178 Posts	With the car moving, the flow of air through the front bumper should keep it relatively accurate, although I suspect mine still reads a couple of degrees on the warm side. As soon as the car is stopped, the flow of air stops and the oven-effect will mean the air within the front bumper will warm up more than the outside air.

25th August 2016, 17:23	#6
first-things-first Posted a thing or two MG ZT Join Date: Jul 2014 Location: Hornchurch Posts: 1,255 Thanks: 176 Thanked 352 Times in 272 Posts	Quite a few cars have temp sensors below one wing mirror. Might avoid engine heat soak.

26th August 2016, 11:48	#9
7T5 Gets stuck in Rover 75 saloon Join Date: Jul 2015 Location: East Lothian Posts: 838 Thanks: 930 Thanked 246 Times in 185 Posts	I joke with my wife that the temp displayed is the temp in Longbridge