Motor dead/not responding on first use

My motor is not responding or either is dead on its first use. Is there a way to fix a dead motor? Using a 393 motor.

This post is in the IQ topic, but appears to refer to the old 393 motors used with the old cortex system. If this is the case, then be sure the 393 motor is being used in either Port 1 or 10 of the cortex, or you are using an mc29 motor controller. The most common problem with the 393 Motors is the wires shorting out where they exit the motor case. Take a look at the wires on the underside and see if the insulation is broken. When the motor shorts out, it will release the magic smoke from the mc29 motor controller, or a bit of magic smoke from the cortex port 1 or 10.


I have never seen an interior-electronically dead 393 motor in my 3 years using 393 motors in VEX. Could you make sure that this isn’t a wiring issue? Like, grab a 9V battery backup and plug it directly into a motor and see if it moves. If the motor moves then it is a wiring issue and you need to check that the motor is wired correctly, using a motor controller if in ports 2-9, and the port is coded correctly (posting code can be helpful for additional troubleshooting). If the motor doesn’t move with the 9V backup then it’s likely an interior-mechanical issue, or possibly an electronic issue. If its a mechanical issue within the motor, remove the screws on the front plate and see if it looks good. If it looks good and nothing is broken, screw off the back-plate of the motor and take off the plastic gears. There’s a chance those plastic gears may be stripped so look closely and see if it’s alright.

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