Port 6 & 7 Fault

I have a brain that is giving us a problem. Anytime anything is plugged into port 6, nothing in ports 4-6 work. If port 6 is empty, everything seems to work. If anything is plugged into port 6, and the VEXOS utility is open, then ports 4-6 all show question marks. As soon as the device is removed out of port 6, then the other two devices show up and work correctly. This same brain is showing a touch sensor plugged into port 7. There is nothing in port 7. Is there a way to reset the brain?

Hi daddycrusader,

We are sorry that you have encountered this issue. On the VEX IQ Robot Brain, the output ports are grouped into groups of three: ports 1-3 are together, ports 4-6 are together, etc. In each of these groups, in rare circumstances if there is one “misbehaving” sensor, it can confuse the Robot Brain about the entire group. So for example, if there is a misbehaving sensor in Port 4, the Robot Brain might also get confused about Port 5 and 6. Reinstalling / updating the firmware separately on each sensor and Robot Brain can resolve this issue.

To resolve this issue, please disconnect all Smart Motors and sensors from your Robot Brain. Then connect the device that was originally on Port 4 onto Port 1, then connect the Robot Brain to your computer, run the VEXos Utility, and update the firmware on that device if necessary. After the update is complete, please remove this device from Port 1, then connect the device that was originally on Port 5 onto Port 1, then update the firmware using the VEXos Utility.

After this is complete, repeat the process again for the device that was originally on Port 6. Now that the firmware in each motor/sensor has been separately updated, please reconnect all Smart Motors and sensors back to their original ports.

If the problem persists, or if you have any additional questions, please contact our Technical Support folks at support@vex.com or by calling +1-903-453-0802 so we can provide additional assistance for resolving this issue.


  • Art