Strange behavior from VNH5019 driver carrier

Hello Brandon

I have recently purchased a VNH5019 and similar to the fellow you had assisted in this forum my controlled is also acting strange. From what I can tell the chip within the left side of the motor controller has a broken connection to the logic circuit that controls connection to the ground wire, I have had to ground the left motor terminals on the controller based on the direction I was trying to move, this allowed both motors to turn however the left was void of any speed control. I have pictures however I am unable to move them from my phone at the moment, however they are just of me connecting M1B and GND to enable the left motor to go forward and M1A and GND to go back.

If you had any suggestions that would be great.



I moved your post to its own thread since it sounded like you are having an unrelated problem.

The behavior you are describing does sound strange; can you tell me more about your setup? We have a few boards that use the VNH5019 driver, can you specify which one you are using? Could you post some pictures of your setup that show all of your connections as well as some close-up pictures of both sides of your VNH5019 carrier board? Also, what are you using to supply the logic signals to the driver and what signals are you sending in your test?


Hello Brandon

We have been using a Arduino UNO R3 SMD EDITION for our project. As I had mentioned our VNH5019 seems to be unable to control the left side motor on our project, it’s only after I connect the specific port either M1A or M1B to the GND port that the motor begins to function, void of any speed control. We have been using a 3000 mAh NiMH VEX power pack which produces 7.48 volts which if I recall from the user guide fits in the 5.5 - 24V operating range, with an adapter through the power cord plug in the Arduino. For controlling we were using an HC-05 Arduino Bluetooth Module connected to the 5V GND RX and TX ports through the VNH5019, which control two 19:1 Metal Gearmotor 37Dx52L mm Pololu motors.

I’ve included a few images in the google drive folder below, and I will attempt to get more information later.

Thank you for the additional information and pictures. It looks like you are powering your shield from your Arduino; please note that the trace that connects to the small VIN pin on the shield is not intended to handle as much current as the driver. The correct way to use the ARDVIN=VOUT jumper on the VNH5019 shield is to power the shield through the larger VIN and GND pins, then the Arduino will be powered through the small VIN pin. Since the Arduino will not draw as much current as your motors, this does not require nearly as much current to pass through the smaller VIN trace.

Could you try removing your Bluetooth module and running our demo.ino example program from our Dual VNH5019 Motor Driver Shield Arduino library? Also, can you post some pictures of both sides of your VNH5019 shield so we can see your soldering?

By the way, I noticed that your power wires going into your terminal block-to-barrel jack adapter are pretty frayed. You should take some precautions against those two wires shorting together (e.g. tinning the wire with some solder, tightly twisting each wire so there are no stray wires, or trimming the stripped portion so all of the bare wire fits inside of the terminal blocks).


Hey Brandon

I tried moving the battery to the GND VIN connection like you had suggested, it seems that your assumption was correct it seems that the pin was not meant to power the motor shield from the Arduino.

My Bad, know I know for next time.

Thank you for your time.