One possible cause is that your battery is low or the battery can no longer hold a (good) charge. In this case, the TomTom is shutting down because there's not enough battery to keep it running, even though it is plugged into a power source.
To determine if the battery is the cause, try to charge the TomTom battery .... using a (USB) connection to your computer, or a direct power source (i.e. while the TomTom is not being used). Let it charge for a few hours until the batter charge indicator shows that it is fully charged (or just leave it charging overnight). Then, unplug the TomTom from the "charger" and power it up. If the TomTom (battery) doesn't hold a (good) charge, the device will shut down within a few minutes, e.g. 10 mins or much less. When you (then) plug the device into a power source, and it doesn't stay on (i.e. it keeps shutting down after 10 seconds), you can safely conclude that the battery is the cause of your problem.
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One possible cause is that your battery is low or the battery can no longer hold a (good) charge. In this case, the TomTom is shutting down because there's not enough battery to keep it running, even though it is plugged into a power source.
To determine if the battery is the cause, try to charge the TomTom battery .... using a (USB) connection to your computer, or a direct power source (i.e. while the TomTom is not being used). Let it charge for a few hours until the batter charge indicator shows that it is fully charged (or just leave it charging overnight).
Then, unplug the TomTom from the "charger" and power it up. If the TomTom (battery) doesn't hold a (good) charge, the device will shut down within a few minutes, e.g. 10 mins or much less.
When you (then) plug the device into a power source, and it doesn't stay on (i.e. it keeps shutting down after 10 seconds), you can safely conclude that the battery is the cause of your problem.