Grove I2C motor driver hangs

I’ved hooked up a Grove I2C motor driver to a seeeduino Seeeduino Mega. I’m running the standard I2C scanner, and it frequently hangs on Wire.endTransmission();
Oddly, when I remove and reattach the switch-jumper of the Grove motor driver, it will (sometimes) detect the motor board once, but then hang again. I’m quite stumped…

I’ve checked that the seeeduino board is set to 5V, I’ve attached a couple of 2KOhm pull-up resistors to the SDA and SCL lines, and ran it both with and without an external battery powering the motor driver. Any ideas?

Hey ,It requires a 6V to 15V power supply to power the motor, did you power it?

And, i’m sorry maybe you can’t use motor driver without a power.