Compass/ Altimeter retrofit?

[emax]

A conventional compass does not work in a car because magnetic distortions in the vehicle renders the reading unusable. The distortions come from the metal cage you're sitting in, the electronic noise everywhere, your loudspeakers and so on. There are a zillion sources for distortions.

The Grenadier compass ring is stepper-controlled (you can hear it) and thus fed by some µC. I am almost sure the input comes from the GPS controller.

However, a GPS can only calculate a heading/direction when in move.

So I think that the compass stores the last direction value which came from the GPS upon shut down and reuses this value until it receives a new, valid direction value from the GPS. Because it takes a bit for the GPS to be completely "up and running", the steering angle might be used together with the driving velocity to continuously calculate the direction until the GPS is completely up.

So the Grenadier compass is likely a more sophisticated instrument than one might think. You can not easily replace it with some traditional compass. You can try it: put such a compass on your dashboard and when the car moves just look what it does. It's mostly nonsense.

 

[Tmal]

Just go into offroad mode and select one of these two screens
Everything you need and it is free
View attachment 7871592View attachment 7871593

Dave, i've seen that but my issue is that altimeter is off. When i'm at the beach, it says i'm -90 ft. Does any one know how to calibrate it? My dealer said it goes off of the GPS. I can't even find the GPS. Any guidance is helpful.

 

[DenisM]

Dave, i've seen that but my issue is that altimeter is off. When i'm at the beach, it says i'm -90 ft. Does any one know how to calibrate it? My dealer said it goes off of the GPS. I can't even find the GPS. Any guidance is helpful.

I may be way off beam here, but I understood that the gps antenna at least may be under the black composite section above the middle of the windscreen. The gps controller is probably a surface mounted component on the pcb driving the central display unit. I doubt there is, any calibration facility other than perhaps the magic laptop possessed only by Ineos dealers

 

[anand]

Dave, i've seen that but my issue is that altimeter is off. When i'm at the beach, it says i'm -90 ft. Does any one know how to calibrate it? My dealer said it goes off of the GPS. I can't even find the GPS. Any guidance is helpful.

Correct, it is GPS based, and has a variance of ±100ft (or possibly 150ft, but I'm fairly confident it is ±100ft).

The GPS antenna should be under the black "cap" above the windshield along with the Sirius antenna, the "reset" is to drive it somewhere without a GPS signal (like a parking garage or tunnel) and then it will get a "fresh" calibration when it comes back out... in theory