Motor Fix?

I recently got a Vex IQ starter kit with sensors. Since 1 of my motors came broken and is currently being replaced, I made a custom autopilot robot. But as I used it. I noticed that the motors weren’t working as efficiently and they were getting louder. Today, my loudest motor just broke and I’m down to 2 motors. I don’t want to buy new ones if they break after 5 hours of use,(Yeah, I used that robot a lot.) so I was wondering if there was a simple fix for the motors.

Basically what happens is:
-Motors slowly get louder after use. (My autopilot bot never ran into things, it would sense it or hit it with a bumper and back up. The support for the motors was fine. The motors weren’t even doing anything to break them.)
-They start slowing down and running inefficiently.
-They break. (One has.)
When I tell the motor to do something, it just sounds like it is jammed.
There is no problem with the ports or anything.
It just sounds and acts jammed.

Is there a fix for this?

EDIT: I was testing the motor and it was working. But it was at 30% of what is should be. In about 5 seconds it stopped.


We’re sorry that you have encountered these issues. To help resolve this issue and to ensure the motors are preforming as expected, please ensure that your Robot Brain and all of your Smart Motors are running the latest firmware.

To update the firmware on your VEX IQ control system, please download and install the VEX IQ Firmware Update Utility to your Mac or PC. Connect all of your motors, sensors, and Controller to your Robot Brain, then connect your Robot Brain to your computer and launch the VEX IQ Firmware Update Utility. If updates are required, please press the Update All Components button to update all of your devices.

There was a previous Smart Motor firmware bug present in firmware version 1.13 that would cause the Smart Motors to run slower and weaker than expected. This issue was fixed in Robot Brain firmware version 1.14 and newer. If your Smart Motors were running this older firmware, then upgrading the firmware to the latest version will solve this weak motor problem.

If updating the firmware has not resolved the problem, please check whether the same behavior from the Smart Motor occurs when the Smart Motor is moved to different ports on the Robot Brain, as well as if it behaves differently in the Autopilot program, versus a custom user-created program from either ROBOTC or Modkit for VEX.

If the Smart Motor behaves as expected from a ROBOTC or Modkit for VEX program, but appears to be slower/weaker than expected in the Autopilot program, this is likely intentional as a result of the Autopilot exploration algorithm placing the robot in either Random Mode, Spiral Mode, or Lawnmower Mode. For example, when the Autopilot program is in Spiral Mode, one drivetrain motor will always spin slower than the other to ensure that the Autopilot robot drives in spirals. You can read more about how the Autopilot program functions in Section 6.2 of the Control System User Guide.

If you have any additional questions, or if your Smart Motor is still not behaving as expected, please contact our technical support folks at or by calling +1-903-453-0802 so we can provide additional assistance to resolve this issue.


  • Art

I already had updated the firmware.