After my 6000 mile inspection, the dealer rotated my tires and adjusted the air pressure. I now find myself in the situation, where I can either trust my two handheld pressure devices, or the internal car monitoring system. Hereby, I am not so worried about exact measurements, but to have pressures equally distributed. If I pump up all 4 tires the same way (35 psi on the dial, measured the same way), the car monitor shows 35, 34, 34, 33. Any suggestions for calibration (again, not to absolute psi, but to a relative measurement)? Mercedes does not show individual measurements and I am sure that it is for this reason. The system is not accurate enough and will drive drivers like me crazy. The solution could be (Jeep > hint!) to use the "reset" button to average the tire pressures left and right and show the developing differences in the future. But for now ... what choice do I have? Either have "nice and equal" readings with truly different PSI, or the opposite 