A red battery with lightening bolt icon on a LabQuest 2 means that the battery has failed an internal test but the unit is running on AC power. There are several possible causes for this.
     – The battery is missing.
     – The battery contacts are covered and not making a connection.
     – The battery capacitance is too low.
     – The battery voltage is too low.

If the battery icon is red, try the following:
– Verify that the battery is installed properly and that the battery contact points are not covered and are clean.
– Update the software at www.vernier.com/support/updates/labquest/labq2/ (version 2.0.1 and version 2.2.1 are prone to this problem.)
– Allow the unit to charge for 12 hours using the AC adapter that came with the unit.
– Reboot the unit (Home > System > Reboot).

If the battery icon is still red, the battery is likely bad and will need to be replaced. Batteries carry a one year warranty. If the battery is less than a year old, contact Vernier (support@vernier.com) for further assistance.

LabQuest 2 Battery Troubleshooting and FAQs
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