MKR1310 not working w/o battery ?

It seems like the board does not power up unless you have a battery connected in the JST connector ?

According to this it seems like it should work, but the serial port never shows up unless I plug in a battery.

"It is also possible to use the USB port to supply power (5V) to the board; run the board with or without batteries - the choice is yours."

Any suggestions ?

So did some testing: without a battery, there is no 3.3v from the regulator. With a battery there is.

The BQ24195L lipo charger seems to be involved, is there a way to disable it checking VBAT ?

Hi, I'm not exactly sure what the issue is, but I can confirm that the MKR1310 works fine without any battery attached to it. Did you try long-pressing the reset button while connected to USB ? It should then show up as COM device in the Arduino IDE.


I can confirm the MKRWAN 1310 does work on USB without a battery. It even works with 5V in VIN without a battery, I have done both regularly.

Is this a new board or have you had it a while?

How do you know it is not powered up? On battery there is no LED, but the power LED is on when powered via VIN or USB?

As suggested double tap the reset, it should then show in the Arduino IDE. What power is present on VCC when connected via USB, it should be 3v3?

It can’t be the solder link on the underside of the board can it? I can’t seen how that would make a difference in this area?

finally, what code are you running? try a simple sketch, something like LED blink:

This script should work on any arduino and works on my mkrwan 1310.

Sorry for the late reply, never got notified of responses ?
So checked again: my MKR1310 does not show up as serial device, you can't upload anything, and double tapping on reset will not do anything, unless you plug in the battery.
Then everything works as it should.
This board is fairly old, got it soon after they replaced the mkr1300.