MKR1000 Battery not charging

I have the Genuino MKR1000 board and a 3.7 V 1400 mAh battery. When I plug it to the socket the "charge" LED doesn't light up. I leave it connected during hours and it doesn't charge. The battery is not even hot.

  • Why is the battery not charging?
  • Do I need to connect any jumper?


Double check the LIPO connections as some batteries I have come across have the - and + swapped over.

Hey I am facing the same problem; Arduino is not charging the LiPo battery which rated at 3.7v, 1400mAh. Did you fix the problem.

mmpk did you check your connections are the correct way around and is it a proper LIPO ?

Thank you so much @ballscrewbo, for your reply. It is working well now!! :slight_smile: :); Since MKR1000 did not give me any LED indication when I connected LIPO battery I thought it is not working. Later I came to know, it has been designed in that manner to better optimize battery power consumption.

But I have baffled with a strange problem now, it is behaving differently when it connected to a computer vs on a 3.7V, 1400mAh LIPO battery. problem is quite similar to the one mentioned here, on Arduino Uno. But here they suspect drop in voltage as the villain. But my multimeter gives me 3.7V almost always.

I am attaching a small snippet of the code for the reference here. Could you shed some light on this?


LOL never attach code as a picture and always try avoid “snippets”

The forum has code tags ( </> ) to allow you to post sketches and error messages.

Include the whole sketch please and as I have an MKR1000 on my test bed I could maybe try it here.

Thank you so much @ballscrewbob, So swift in replying, I love, respect and appreciate your attitude. the code is bit lengthy that is why I did not attach. I will brief the story first: This involves Arduino-Unity mutual interaction. Arduino is expected to send a set of 5 values (based on inputs from 5 analog pins) upon receiving correct instruction from Unity.

My apologies, I could not embed the code here since it is bit lengthy. so I am attaching it as .txt file

The values I am getting at Unity over WiFi on battery mode are “- 214783646”, does it signify something (I believe it as the minimum value of 32 bit signed int, what may be the possible cases to trigger this)?

Code.txt (10 KB)

I have no experience with UNITY but it appears to be a higher level of the program "Processing"

The sketch compiles just fine but I dont appear to be able to send or receive from or to the MKR using it. Tried a couple of my "GOTO" terminal programs. Both IP or COM ports connections are refused. just maybe the number you are getting is at a timeout point ?

Checked the MKR here out and send & receive work fine with any other two way serial sketch or IP communications sketch

Based on testing here it is almost certainly an issue within the sketch or the way UNITY treats numbers.