Problem with Pololu Dual MC33926 Motor Driver Shield for Arduino


its about the MC33926 Motor Driver Shield which I am using on an Arduino Uno.
Its soldered properly. The multimeter proves the correct current on the pins (4, 7, 8, 9, 10, and 12), but all motor outputs remain constantly on 0, both with the approved demo as with a variety of personal sketches.
I have powered the shield with DC power adaptors of 2A/12V and 5A/12V and did not yet connect a motor (which would be those

Since I experienced similar problems earlier with the Dual MC33926 Motor Driver Carrier and the Pololu High-Power Motor Driver 18v15, I wonder if it might simply be an issue of my power supply.

I would be very happy about your recommendation about finding the error and eventually about better powering the shield.

Best wishes,


Many of your soldered joints do not look like they would make a reliable electrical connection with the PCB. The Adafruit Guide To Excellent Soldering has examples of good and bad soldering joints in the Common Soldering Problemssection. Can you try retouching your connections so they look like the good examples in the guide and see if you still encounter problems? (In particular, you should not see any gaps around the pinholes and the joints should look smooth.) If you are still having problems, could you please post pictures of the retouched solder joints here?

By the way, the 37D mm gearmotors have a 5A stall (when supplied with 12V), so I expect your 5A/12V supply and the High-Power Motor Driver 18v15 to work outright for controlling one. However, if you are not planning on loading your gearmotor much, you should also be able to use the lower power MC33926 shield and 2A/12V supply, too.


Thank you so much Jon!

It´s a bit embarrassing, but you were 100% right: poor soldering. The large GND has not been connected properly. Not it is and everything runs well.

Best wishes,