How Does Geotab Device Calculate Odometer?

Applies To

  • GO Device
  • Odometer
  • Engine Measurement


There are few priorities when we try to get the odometer value for a vehicle:

  1. If we can read the odometer value from the engine, we will use the value from the engine and there will be no calculation for raw odometer.
  2. If we cannot read the odometer from the engine, we will use the GPS odometer, this involves calculation.
  • If ignition is detected, the trip history will be considered as driving and the distance on the map will be considered in the GPS odometer.
  • If ignition is not able to be detected directly from the engine:

a. Trip Tracking. If the vehicle is known to have engine based or three wire ignition, it will not set the ignition flag.
The system will consider the ignition as on when accelerometer detects movement of a certain amount or the GPS is powered on for a period of time.

b. Two-Wire. Under two-wire installation, the device will only be able to detect voltage. The device will automatically calculate the average voltage for ignition. It will set the ignition flag to ON if the voltage reaches the threshold.

If a vehicle is on a boat or being towed, it will trigger Trip Tracking if it is not known to have engine based ignition.

Additional Notes

The Two-Wire and Trip Tacking can be disabled by adding the below custom parameter to the vehicle:
<GoParameters><Parameter Description="Disable Two Wire and Trip Tracking" Bytes="04" Offset="64"/></GoParameters>