I made my first flights today and at times the lights on the Mavic were blinking red and at times the one on the back was green.  I was in beginner mode and only had time to fly about 10 minutes with each battery.  Just wanted to check everything out.  Flights went well otherwise.  I have tried to search for an answer with no luck.  What would cause this?

Sounds it could be a false low battery warning that is being triggered because you might be flying in a low temp environment.  In a low temp environment of the battery is cold the voltage will sag because the internal resistance is higher.  I have seen this my other rigs.  What probably happens is, if you push up the power a little you are increase the current flow and this will cause the voltage in each cell to sag to below the 3.5 threashold and will trigger battery warnings.  Lipo batteries are not at their optimum discharge ability until reaching 40 to 50C

Did you charge the batteries before using them? Here's a link to the Mavic's user manual, and the specific portion you should look at is on page 12 (Flight Status Indicator). Slow red flashing means the battery is low, and fast red flashing means that the battery is critically low. The batteries aren't delivered fully charged because it's not good to keep them that way for long periods of time and they have a built-in ability to discharge themselves after a certain number of days.

P.S. Be sure to also charge your controller, because it also isn't delivered fully charged.

DroneFlying Posted at 2017-2-11 17:39
Did you charge the batteries before using them? Here's a link to the Mavic's user manual, and the specific portion you should look at is on page 12 (Flight Status Indicator). Slow red flashing means the battery is low, and fast red flashing means that the battery is critically low. The batteries aren't delivered fully charged because it's not good to keep them that way for long periods of time and they have a built-in ability to discharge themselves after a certain number of days.

P.S. Be sure to also charge your controller, because it also isn't delivered fully charged.

Thanks.
I should have provided the following in the original post.  I received the Mavic about a month ago and charged the batteries and the controller.  We have had some terrible weather since, but 2 days ago it looked like it would improve today.  So I charged everything 2 days ago.  The air temp today was 45 F and about a 8mph breeze.  Each battery was barely warm to the touch after a short flight and the Mavic it self was the same.
The controller showed the battery % at 59% for one, 85% for one and the last one at 78% before the flights.  I was also flying very slowly.
Thanks for the replies.....I can see how it could have been a low battery signal.

He Gramps did you ever figure this out. I have eight green blinks then two longer red blinks but iut seems to fly OK. Recalibrated the IMU and Compass and the look good. No other problem indicators.