Tpms

Have had the car a little over 4 months now and had not checked the tyre pressures since first getting the car and setting the TPMS. Yesterday as I was checking the pressures in the other family cars I thought I should check the A6 as well, although I had had no TPMS warning. I was surprised to found they were all reading about 1.8 Bar when they should be at 2.2/2.1 Bar (ie about 10% below where they should be). Makes me think that either the TPMS on my car is not functioning correctly or the level of tolerance before the alert sounds is quite large and manually checking the pressures on occasion should not be forgotten.

I believe that the Audi system works off the wheel speed/ABS sensors similar to other manufacturers.

You car may have been set with them a bit low, in which case it will not flag them as a problem. It only alerts you in the event of a difference to one or more wheels.

Mine went off a few weeks ago on the M6. Luckily I was close to a services so stopped and checked pressures. All were fine! I just reset the system and it hasn't made a noise since. I try to check my pressures once a fortnight.