Speedometer analog vs digital

Is the digital speed sourced from the analog speedometer or a computation via navigational gps ? No speed posted on any of the navigational screens so thought maybe digital speed was a product of the navigational system.Thanx in advance

 

Nothing should be done from gps. It is done at the wheel sensor

 

Signal from speed sensor sent to ecu and

1. Displayed on digital display
2. Sent to stepper analog motor moving needle

No GPS signal guiding your speed (would suck if you couldn't see how fast you were going in a long tunnel).

 

Thank U Thought there would be a MPH readout somewhere on the navigational screen like most other brands navigational systems. My aftermarket Pioneer navigation in my 2005 Taco had a MPH reading on the screen which was nice to have a cross reference for speed. No drama. Thanx again

 

Related to this, my analog speedometer is 1-2 miles higher than my digital readout. Which is correct? Is there a way to get these perfectly aligned? Thanks

 

Neither. Not easily.