My windscreen was frozen this morning and when I poured warm water on to defrost it, the water started to freeze again. Eventually I got into the car and I noticed the temperature reading on the dash was 3.5 degrees. I thought, no it's not, it can't be any higher than 0 degrees.

A building beside us has one of those big digital clock/temp signs on it and it read 1 degree. So checked the reading on my wife's Megane and it was fluctuating between 0 and 1 degree. Looks like the Octy display isn't accurate.

Has anyone else found this problem and does anyone know if it can be corrected?

Do not know on the accuracy but water freezes from 4 degrees down

The temp sensor is buried inside the door mirror so is probably being shielded from wind chill effect.

yep , like jjc says..water reaches maximum density at +4'C and will start to freeze .

'warm/tepid' water will actually begin freeze faster than cold water.

..strange stuff that H2O

The temp sensor is buried inside the door mirror so is probably being shielded from wind chill effect.

yep ' date=' like jjc says..water reaches maximum density at +4'C and will start to freeze .

'warm/tepid' water will actually begin freeze faster than cold water.

..strange stuff that H2O[/quote']

And then you get all that lark about differences in air temperature and ground temperature. Hence the warnings some days to beware black ice even when the temp above ground seems okay. The thermometer can only be a rough guide. [And also book says it doesn't register accurately till you've been on the road a few minutes.]

yep ' date=' like jjc says..water reaches maximum density at +4'C and will start to freeze .

[/quote']

So thats why exterior temp. displays start to show show their ice crystal/snowflake symbols at +5C

Still not convinced and the reading doesn't change any when I get on the road either. Interesting point about water frezzing from 4 degrees down though.

Still not convinced and the reading doesn't change any when I get on the road either. Interesting point about water frezzing from 4 degrees down though.

Depends what's in it. Only pure distilled water has an official freezing point of 0 degrees. Hence salt or antifreeze in the water makes it have to be colder to freeze. Also when it comes down to 0, it has to lose more "energy" to turn solid, still at 0, then it can carry on getting colder as a solid. Even though cooler, the solid is "bigger" than the same amount of liquid, so it burst yer pipes! Aaargh!!

Depends what's in it. Only pure distilled water has an official freezing point of 0 degrees. Hence salt or antifreeze in the water makes it have to be colder to freeze. Also when it comes down to 0, it has to lose more "energy" to turn solid, still at 0, then it can carry on getting colder as a solid. Even though cooler, the solid is "bigger" than the same amount of liquid, so it burst yer pipes! Aaargh!!

My pipes are burstin' right now. Back in a min!

Still not convinced and the reading doesn't change any when I get on the road either. Interesting point about water frezzing from 4 degrees down though.

Hot or cold, the temp gauge on my Octy2 will change by a couple of degrees once on the move.

Mine's just plain knackered. It read -10 the other day and the forecast was for 13 deg and sunny!

Great when the suns out and the climate control wont use aircon as it thinks the air outside is cold enough to use....

Getting it sorted next time it's in btu I thought the temp sensor was in the front bumper on the new Octy