Here are some common issues we see using and charging Phantom 4 RTK batteries
I charged my batteries last night, but now they are dead or only half full?
When using the multi-battery hub, check that it is in charging mode, not storage mode. A slide switch is on the hub next to where the 10-pin cable plugs in. Be sure to check the slide switch each time you charge your batteries, as the switch can sometimes change modes when replaced or removed from the carrying case. If all batteries light up when connected to the hub, you are in storage mode.
I just finished a flight, and now my batteries won't charge.
If you connect the battery shortly after a flight, the battery has a safety mode engaged that prevents charging until the battery has cooled down. A single LED will flash, which looks like it is charging, but it is LED4, not LED1 that is lighting up. Remove the battery for a few minutes, then try charging it again.
What should I do if my battery is unresponsive?
It is most likely defective if your battery is brand new and won't charge directly off the 10 PIN cable. Check if another battery charges using the same charging cords and hubs to rule out any other sources of the issue. Contact DJI Support to replace the battery.
If the battery used to charge and doesn't charge anymore, check that the battery has not swelled and that the pins are not damaged or fouled with foreign material. If they are clear and won't charge, you may have a battery fault from which the battery management system (BMS) is saving you. Contact DJI Support to replace the battery.
I still can't do it!
We wrote these articles to equip you with everything you need to get the job done on your own, but we understand that sometimes this isn't sufficient.
If you're stuck, the Propeller hardware support team may be able to help. You can contact our support team by emailing firstname.lastname@example.org.