Altimeter issues. Reset/Calibration possible?

[Tom109]

The altimeter is linked into the GPS system of the Grenadier. Lose GPS and it goes out. —— on both the infotainment and the compass.

The Baltimore tunnel would tell you otherwise.

Driving through the Baltimore Tunnel yesterday, the altimeter showed -100ft while the GPS teltale
At the top of the screen showed two hash marks. It is definitely barometric.

 

[Stu_Barnes]

The Baltimore tunnel would tell you otherwise.

Theres GNSS as well as GPS. If your tunnel has underground GNSS repeaters then it knows where it is. At least that’s how I understand things to be. Next time you’re there see if the lat and long are still working.

HAL9000 almost always knows.

(I think this is in danger of being the geekiest thread on the forum )

 

[DenisM]

Driving through the Baltimore Tunnel yesterday, the altimeter showed -100ft while the GPS teltale
At the top of the screen showed two hash marks. It is definitely barometric.

The next phase is to take several readings I.e. is the -100' reading at the midpoint and what are the entry and exit altitude readings?