Hey @Gus_Rubio10 ,

Great question! Thank you for asking it in our community. There are a few common reasons why a GO device may fail to read the VIN from a vehicle's computer. I used an AI tool to help compile this answer, so please let me know if anything needs clarification.

The GO device reads the VIN by querying the engine ECU over the CAN bus. Whether this succeeds depends on how the vehicle manufacturer implemented that part of the ECU firmware. The most common reasons it fails are:

- VIN not programmed in the engine ECU — especially after an ECM replacement, the VIN sometimes needs to be manually re-entered using manufacturer diagnostic software and is often skipped
- The ECU returns a manufacturer-internal ID instead of the ISO VIN — some manufacturers store an internal build or calibration number in the VIN register rather than the standard 17-character VIN
- ECU security lockout — newer ECU firmware versions on some makes require an authenticated diagnostic session before exposing the VIN. Without it, the ECU ignores the request entirely
- CAN bus connection issue — if the device is operating in two-wire mode or is connected to the wrong CAN segment, it has no path to the engine ECU

It is also possible a loose installation is causing this issue. its hard to say without looking the specific case but I hope this helps give you some things to look into. If the engine VIN cannot be read automatically, the most reliable workaround is to enter it manually in the device settings in MyGeotab.

Please let us know if you have any follow-up questions - happy to help!

Have a great day!
Eishi FUN