Why doesn't my odometer match my dashboard?
Last updated September 4, 2025
For most vehicles there will only be a small difference between the engine odometer and dashboard odometer values. If the vehicle has had extensive engine work done such as a rebuild, then the engine odometer can be reset to zero and that difference from the dash odometer can be pretty large.
The Canadian regulations mirror FMCSA Regulations which require that the odometer readings come from the engine’s ECM.
- Check that the ELD is linked correctly to the vehicle’s engine's ECM. The vehicle distance information can be acquired from the engine's ECM as specified in provision 4.2 of this Standard:
- The ELD must monitor the engine's ECM’s odometer message broadcast and use it to record total vehicle distance information; and
- The ELD must use the odometer message to determine accumulated vehicle distance since the engine’s last power on the instance.
The ELD mandate is very specific about how ELDs should get the odometer reading for e-logs. The engine odometer is based on engine shaft rotations, and is more accurate than a dashboard odometer, which is based on wheel shaft rotations that are affected by changes in tire size and pressure.
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