I understand when you plug the sprocket to charge LED light turns on and turns off immediately.
Don't worry I'll try to help you out.
Did you make any changes to your printer?
Have you tried charging with a different wall outlet or a different adapter?
Try the steps recommended below.
Please try few steps recommended below.
1. Reset the Sprocket unit by placing a push-pin or needle into the small hole on the rear of the unit. (Reset instructions in the support doc HERE)
2. Plug in the Sprocket unit with the provided micro-USB cable. Connect to either a computer USB port or USB wall charger.
3. Allow the Sprocket unit to charge for 10 minutes. Note: A call back may be required in these instances.
4. Power on the Sprocket unit by pressing/holding the power button for 3 seconds.
5. A white LED should illuminate on the rear of the unit if power up is successful.
6. Remind the customer to charge their Sprocket for an additional 60-90 minutes to enable a full battery charge.
If the issue persists, check the settings:
By default, the Sprocket is set to turn off after 5 minutes. You can change when the printer automatically turns off using the HP sprocket app.
1. Turn on the Sprocket.
2. On your mobile device, open the HP sprocket app.
3. Tap the Menu icon , and then tap sprocket.
4. Tap Printer Settings.
The Sprocket information screen displays.
5. Tap Auto Off under the Settings section.
6. Select when you want the Sprocket to automatically turn off, and then tap the Back arrow to save the setting.
If the issue still persists uninstall the sprocket app and reinstall the app and try updating the sprocket firmware from the sprocket app and check if it helps.
Open Sprocket app go to menu-->Sprocket---> Printers; A blue firmware update link will be present if an update is available.
Refer this article to know more information about using sprocket printer.
Also, refer the printer user guide for more information.
Please let me know if this resolves the issue, or if you require further assistance!
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