Motor not seen (no device) or I2C error

We are having trouble with one of our motors. Sometimes when we reboot the brain it says I2C error ports 10-12. We have a motor in port 11. It offers to have us reboot. Usually after rebooting the error is not there but going through diagnostics it shows nothing in the port. Hooking up to a computer with the Vex IQ Updater also does not see the motor.

I had read somewhere that one way to get past I2C errors is to unplug everything and plug the problem device into port 1. It doesn’t show up there either.

The motor was working the last time we used it a couple of days ago. What might we have done to make this happen? How can we resolve the issue?

It reminds me a little of an issue another team was having at our challenge last Saturday where the motor would say it’s a bumper no matter what port it was in. Sometimes the motor that thought it was a bumper would swap around and once a couple of motors said they were bumpers. I don’t know why these parts seem so touchy or what we’re doing that we shouldn’t be doing to trigger this trouble.

HI jla,

We’re sorry that you have encountered this issue. Since you have already tried to reinstall the firmware on Port 1, please contact VEX Technical Support at or by calling +1-903-453-0802 so we can help resolve this situation.


  • Art