Quote:
Originally Posted by Frqnj
The recommended tire pressures on the idrive system and those listed on the door jam are extremely discordant and not to mention ever changing on the idrive system. BMW NA technical support couldn’t give me a good answer.
I have the 21” all season run flat option.
Door jam lists pressure as 32 psi front 38 rear
Idrive screen varies between 40-43 psi front 45-50 psi rear
What gives?  |
As long as the tire size and type is set appropriately in iDrive, the recommended tire pressures should be correct and take the current outdoor and current tire temperatures to make a recommendation based on the real-time conditions.
If you check the recommendation right after a cold start you should see it pretty close if not spot on the door tag, at least that's been my experience. I did have the tire size correct from factory but it was set to summer and I had to switch it to the winter / all season setting.
The dealerships seem to think the recommendation is black magic / technology stupidity, but it's been proven that it takes the pressure, outdoor temp, and tire air temp into account by a few forum members.
There actually is a way to code the tire pressure display to show both the pressure and temps, but from the factory the car still has that data and uses it even though it's not shown to the end user.