0% Battery, 5G21 Gateway

  • 14 June 2021
  • 8 replies


LOVE my new T-Mobile internet service BUT the chimney has been plugged in for 3 days and display still reads, “Battery 0%”.

Does that mean it’s a defective unit or maybe no battery was installed?

Speaking of battery, can you tell me what UPS units are compatible with the external UPS port on the T-Mobile hardware?



8 replies

Userlevel 1

Sounds like you need to return your gateway and get another one. As for battery backup, neither T-mobile nor Nokia would let me know of an UPS that actually plugs into the UPS port. I ended up buying a 12 volt 35 ampere hour battery, a battery charger and a 300 watt DC to ac invertor that will provide at least 6 hours of ac power to power my gateway, router, alarm system, Smart things hub, television and laptop computer. If power is out or longer than 6 hours, I connect a portable 100 watt solar panel.

Initially, I bought this to power just the gateway for 10 hours:

Userlevel 5
Badge +4

I got mine a four days ago, love it also, and the indicator on top shows a full battery and says 100% now, but I remember when I was charging, even after a full hour with it on, it still said zero. Have you tried pressing the on/off button to the off position, and then turning it on again, rebooting? (I know you probably did, but it seemed like after I did that it changed.)

As you probably know, the battery functions only for storing your configuration, I think, and more importantly allowing you to carry it around the house, tapping the top to see where you can put it to get the most bars. It won’t act as a backup in the event of a power failure.

When my tmobile internet device is fully charged, do i need to unplug it or just keep it plug?

Userlevel 5
Badge +4

When my tmobile internet device is fully charged, do i need to unplug it or just keep it plug?

You have to keep it plugged in. It will not work on the battery. When unplugged, the battery will let you carry it around to tap the top and find a location and orientation for the gateway that has the most bars, meaning the best signal strength. But then you have to plug it in to get internet.

Thank you..Appreciate much

How do you recharge your wifi unit if it stay plugged in to the eletric wall socket?

My tower was showing 0% battery. I turned it off then on and in about one minute it went to 37%. This was recommended by an earlier suggestion. 

I have a Nokia 5g21 ,   for some reason T-Mobile has decided to disable the backup battery on this model ....  no idea why ,   I can't think of any reason that makes sense.