Tyre pressure sensors

mjrennie · Post by **mjrennie** » Fri Jul 26, 2019 12:15 pm

Anyone know how to reset these? Had a smart repair done this morning, all good. Yellow light won't go off even though the pressures all show normal. Annoying.

mjrennie · Post by **mjrennie** » Fri Jul 26, 2019 2:26 pm

Ah. Quite easy. Select in the dash binnacle window...

Paul1970 · Post by **Paul1970** » Sat Jul 27, 2019 9:10 am

When I start a journey the front and rear pressures usually show the same reading. By the time I end my journey they often have 4 different readings. Is this normal?

One tyre started at 36 the other day and finished on 41 (that was the hottest day of the year though but it seems quite a big change)

Wing Commander · Post by **Wing Commander** » Sat Jul 27, 2019 9:41 am

As they warm up, on my car, they often move up a PSI at slightly different times. So at one point, they might be 30, 30, 31, 32 and then settle down to say 30, 30, 32, 32. On the same axle, they are not more than one PSI apart at any one time.

Ian.g · Post by **Ian.g** » Sat Jul 27, 2019 11:24 am

When I had new tyres (put on at OPC) the readings were all wildly different. I checked the with a pressure gauge - and they were all completely different. I thought that the OPC might make more effort to get them correct. Anyway, I put some more air in and got them all correct. They do vary with temperature - if it is a cold morning then they are lower. They are higher later in the day and after driving. They should be pretty much the same across each axle though. Mine are 2.5 bar rear and 2.3 bar front for 20in wheels on an SD.

Paul · Post by **Paul** » Sat Jul 27, 2019 12:48 pm

As Ian says
I check mine regularly (monthly) with a handheld guage. The TPM reads 2.3 front and 2.5 rear which will go up to 2.5 and 2.7 when being driven. It did get to 2.6 / 2.8 on Thursday but in all cases it stays constant side to side.
You’ll find you beed to out a drop in when winter comes and take a drop out as summer approaches.
I also find it will show 0.1 different if parked sideways in the sun.

gasgas1 · Post by **gasgas1** » Sat Jul 27, 2019 5:55 pm

pressures should only be set when tyres are cold.

Paul · Post by **Paul** » Sat Jul 27, 2019 7:55 pm

gasgas1 wrote: ↑Sat Jul 27, 2019 5:55 pm pressures should only be set when tyres are cold.

So true....but define “cold” on a winter’s morning...or a summer am.....

I find around 0.1 / 0.2 bar difference between, say January and July (2-5 degrees / 15 degrees)

SAC1 · Post by **SAC1** » Sat Jul 27, 2019 8:11 pm

This covers it......

https://www.tyresizecalculator.com/tyre ... the-summer

Paul · Post by **Paul** » Sat Jul 27, 2019 8:28 pm

Yup, 0.1 bar per 10 degrees ambient....measured prior to driving first thing in the morning.

Tyre pressure sensors

Porsche Macan Owners Club

Follow Porsche Macan Forums