The Digital Matter devices use Digital Inputs to show physical inputs (ignition, input 1, etc) and statuses (battery low, external power low etc).

The MyGeotab 3rd party API allows these inputs and statuses to be mapped to Auxiliaries. There are 8 Auxiliaries available.

This describes those mappings:

Input or Status Name Digital Matter Location Mapped to here in MyGeotab
Ignition Digital Input 0 Ignition
Input 1 Digital Input 1 Aux 1
Input 2 Digital Input 2 Aux 2
Input 3 Digital Input 3 Aux 3
Input 4 Digital Input 4 Aux 4
External Battery Status Status Flag 2 (TRUE if external power is present) Aux 5 (TRUE if external power is NOT PRESENT)
Internal Battery Status Status Flag 1 (TRUE if internal battery is GOOD) Aux 6 (TRUE if internal battery is NOT GOOD)
Input 7 Digital Input 7 Aux 7
Input 8 Digital Input 8 Aux 8

Note that Aux 5 and Aux 6 have "special meanings", and are not just mapped through from the digital inputs.