Battery will not take a charge or unit will not turn on

19 Jan 2018

UPDATE: An older unit may not charge a newer battery pack without first being updated. See the following web page for details.

Firmware updates for new battery packs

Aug 2014

If the battery will not take a charge or the unit will not turn on even after charging for a while, some possible causes and solutions are as follows.

Perform a Hard Reset by pressing and holding the Power button for a full count of 20 seconds. If the unit was running on external power before, the screen will flash off and on two or three times while holding the Power button, and even a blue screen with sliders will appear. Keep holding the Power button even until the blue screen disappears, and then release. You then may again need to hold the Power button for 2 - 3 seconds before the unit will start booting.

An old wall charger may not provide enough maximum current output to charge a newer product model. See the following web page for more information.

Old charger will not charge newer product model

With an OS release less than 1.6.1 installed, a unit may not turn on if the battery has been severely depleted to enter "recovery mode". Removing or swapping the battery may get the unit to turn on, but the original battery can take 2 to 4 hours (possibly even overnight) on external power before it will even begin to show a change in charge status and then operate (even briefly) without an external power source. When a battery is in such a condition, it is recommended to leave external power attached over night or weekend (as is usually recommended for between work days) to ensure full charge the next work day.

Make sure you are using the correct charger for the product. It should provide a 12V output at 18 - 20 watts (1500 - 1700 mA). Some chargers for other products may be similar, but not provide the correct output. Even chargers for our own older product models may provide the correct voltage, but not enough wattage (amperage) to fully charge the battery within a reasonable amount of time.

To best avoid such a condition in the future, charge every night and weekend. For short term storage (such as less than 2 weeks), perform a full Power Off (hold the Power button for 2-3 seconds and select the option). For long term storage of any unit (such as more than 2 weeks), charge the battery to full then remove and store separately.

WARNING: Never pull the battery while the unit is running (even if frozen). Instead, perform a Hard Reset (by holding the Power button for a full count of 20 seconds) or full Power Off. Removing the battery while the unit is running could lead to internal storage memory corruption with symptoms as follows.

Installing our latest OS release 1.6.1 or higher implements improvements when in such a condition (at least gives some indication of life), as described at the following web page.

Red battery screen appears on Archer 2 or Allegro 2

The latest OS update is available at the following web pages for each product model.

Additional ideas and information for our older products (which may still apply but only to a limited extent thanks to later improvements) are provided at this web page.

Battery pack will not charge to full

If the problem still occurs, please contact support@junipersys.com.