Please check Retrotec USB chargers for the marking shown in the below image.
 

 

There was an issue with some past DM32 chargers that resulted in not being able to charge the gauge from a fully depleted (0%) battery level. There will be a letter in the lower right-hand corner. If it has a “D” shown please notify [email protected].
 
Affected chargers are from 2018 or prior. Retrotec can replace the charger during your DM32's recommended 5-year calibration service. 

Please contact [email protected] if your gauge isn't working for any other reason, as well.