Updated my Mavic the other day without any issues, been out with it today two flights with two batterys no issue. Next battery i used when it was switched on came up on my screen as needing update, as i only had 53% left on the controller thought i would switch off and do at home. Got to 99% update and just sat there for three hours, decided to re-try but the battery has two lights on it that won't go out no matter what i do, it will not charge and it says battery below 50% if i try to go through the update. All my other batterys are fine without issue only thing i can think of is leaving it in the Mavic till its totaly discharged

Hi,

I had the same fortunately I had battery charged enough to do upgrade once more time. Are you sure it is not charging? Maybe it is not showing but charging. I would give a try to leave it on charger for while like 30 mins and then retry.

David

U have to try on dji assistant 2 on computer make sure u put battery in ac and run fw update hopefully the battery has over a 50% charge

Had the same problem with the latest update. Three of four batteries worked fine, the last stucked with two LEDs on.
Problem: During the update the battery drops below 50% and pauses the update.
Solution: Charge the battery and connect to your PC and run DJI Assistant 2. It will show "update available" or similar. That will solve the problem and battery will recover.

It worked for me but.... I used a third party charger. It was the big bad boy with capacity to load three of the batteries at the same time. DJI Charger flashed red and did not charge the battery. But the other charger did. The two middle LEDs were still on and there was no optical indication that the battery was charging.
The charger clearly showed that the battery was charging. Once its LED turned to green I put the battery into my Mavic (which immediately turned on) and connected it to my PC. Assistant 2 showed "update available". I hit start and thats it. Battery recovered.

Hope it helps.

Please remove the battery and try to charge it for about 2 hours, and then mount the battery to the aircraft, connect your drone to the computer and try to upgrade it via DJI Assistant 2 again. The middle 2 LED lights will keep lighting and the power button of the battery will not work until the upgrade is successful.