18v15 suddenly stopped working

Recently I bought the “Pololu 18v15, 5.5-30V, 15A Motor Controller”
when i got it it worked. and i varnished the underside of the pcb to prevent shortcircuits.
however when i used it in my project it suddenly failed. when I plug in the USB only the green light goes on.
the MC stopped working when it was idle, the power was supplied by a 18.5 V battery and the board was disconnected from the motor and did not receive an RC signal.
before this the board sometimes did not run the motor when an RC signal or USB serial told it to.
can this be fixed? And if not can i return the item for a replacement?


I am sorry to hear about your board. We have more than one product with 18v15 in its name, but it sounds like you are talking about our Pololu Simple High-Power Motor Controller 18v15. Can you confirm if that is the case?

Regardless, can you tell me more about how you were using the board and when it failed (e.g. was this right after connecting battery power, several seconds after controlling a motor, connecting the board to your computer, etc.)? Can you post pictures that clearly show both sides your board? If you have a schematic that shows your connections to the motor controller, that would help, too.

Also, if you have the Simple Motor Controller, is it able to be recognized by your computer? Specifically, are you able to see signs of the Simple Motor Controller listed as a device in your computer’s Device Manager? You can read about how to check for that under the 'Using the Serial Interface" section of the Simple Motor Controller’s user’s guide, which you can find under the Resources tab of its product page.


The device does not schow up in device manager. Only the green light goes on.
It doesn’t show up in the simple motor control center program either.

the board failed when:
the batter was plugged in, the battery was plugged in for a few minutes. the motor was plugged out for more than a minute.

before that the board was plugged in with USB into the computer and was changed from serial/usb mode to r/c mode and disconnected.

ps. I also removed the varnish.

Unfortunately, it is not clear what the issue might have been, but it does sound like your controller could be beyond repair.

One thing you might try as a last ditch effort is to try restarting your computer and switching to different USB ports. If that doesn’t work, please send us an email with your salesorder information.