I installed winter rims on my 2011 Q5 (premium plus) yesterday and had a stock tire repaired due to a nail. When the tire guy removed the rubber from the rim i noticed there was no tire pressure sensor in the rim. I was under the impression the Q5 used sensors to monitor the tire pressure. Is this correct?

The winter tires i installed on the new rims did not have any sensors and i do not have any indicators on the dash advising me that sensors are not present.

What am i missing here?

 

There's an old post in the forum, from some oddball named Warcity, about tire pressure. The essence is that the 2010 and onwards, don't have direct tire pressure monitors but instead use indirect sensors related to the ABS. The benefit of this is that you don't have to concern yourself with 4 extra parts. The disadvantage is that your car will never know the exact pressure of each wheel (it will only sense the relative pressure difference. I'm guessing that as the tire loses air, the car senses a change in weight distribution, but you can google it.) I had a leak with one of the tires and the car sensed it.
The other part with this system is that you have to set the car's baseline pressure. i.e. manually check the pressure of each tire (make sure it's at the car's recommended value) either at a gas station or with your own pressure gauge. Then go in the MMI car setup and set your tire pressure.

 

Thanks LMcQueen for the detailed reply. I suspected that was the case, but I've been reading so many posts where people are ordering sensors with their winter tires that i thought i was missing something. I'll do a search for Warcity's post and read it.

 

Yes that oddball was moi and LMcQueen is correct.

 

Oddball?

 

The other day my TPMS flashed that all my tires were "off." What happened was that my all seasons were 18" but the recent winters are only 17". I hadn't bothered to reset the MMI when I got the tires changed last week. Should have practised what I preached.
Happy Holidays and safe driving.

 

Interesting, we went to 17" on our Q5 with no problems since they were the same overall diameter as the OEM 18". What size 17" tires did you buy? FWIW, we're rolling with 235/65-17 Bridgestone Blizzak DM-V1s for our winter tires. The OE rubber doughnuts are Continental CrossContacts sized 235/60-18.