Tyre pressure issues

[GrahamHill56]

Well I've been a Cayman owner (and 1st time Porsche owner) for about a month now & I'm confused/receiving conflicting information.

 

The hand book & info in the car gives 2 options for 20 Summer Tyres

Normal           2.3 bar front & rear

Comfort          2.1 bar front & rear

For the first month I used 2.3 (using a traditional tyre pressure gauge)

At the weekend I've dropped it to 2.1 all round to see if it is a little more comfortable. The display on the dash seemed to agree showing 2.2 all round.

Today I have had a warning pop up saying that the rears are 0.3 bar below what they should be, but the display on the dash is still showing 2.2 & 2.1 per my tyre gauge!

So I called in at our local Porsche Centre @ Tewkesbury & the service guy told me 

"ignore the manual"

"because the rears are larger than the front, then the rears should be a little higher"

NB He couldn't/wouldn't tell me what pressure to use!

"the display to rely on is the one saying how much air to add or take out"

 

I'm inclined to ignore the dash display & just rely on my tyre gauge & just use the dash display as a guide.

 

Leaves me somewhat unimpressed by Porsche service.

 

Thanks for any input

Graham

[Dougle_turbo]

Did you get the warning when you first started up? Or was it after you had been driving for a while?

[S999sws]

Have you set the tyre type to comfort mode?

This is done on the steering wheel lever under settings in the right hand display. 
SWS 

[GrahamHill56]

Yes I have set the dash setting to comfort.

The gauge shows

Front Axle 2.2 & 2.3

Rear Axle 2.3 & 2.3

The fill display shows

Front Axle +0.2 & +0.3

Rear Axle -0.3 & -0.3

So if I'm reading this correctly 

I could reduce the fronts to 2.0

but the rears are asking for 0.3 bar in each tyre taking them up to 2.6 bar for each tyre!

The manual says that the comfort pressures are 2.1 bar all round!

So I'm still confused

[S999sws]

Another thought, if I remember correctly you can only have the comfort setting if you have 20 in wheels. You do have this size don’t you. 
also on mine it doesn’t say “comfort partly load”. Just comfort mode. I wonder if this extra bit of info on yours  has anything to do with it..

SWS 

[GrahamHill56]

If anyone's interested I eventually had it looked at by Porsche Centre Tewkesbury & they discovered that the onboard "computer" had the wrong tyre pressure on it's database, so it was replaced under warranty thankfully.