N20 Motor Not Starting After Connecting to Arduino 3.3V and GND Pins—Possible Damage?

A hobby N20 brushed DC gear motor rated for 3 to 5 volts was connected directly between an Arduino 3.3V pin and ground without using a digital or analog I/O pin. Initially, the motor operated but then stopped working and failed to start even when powered by a 4-cell battery pack. The motor is a normal brushed DC type, not a stepper or servo. Directly powering motors from Arduino pins is discouraged due to insufficient current capacity and risk of damage. Possible causes for the motor failure include internal wiring breakage, brush or commutator issues, or mechanical jamming in the gearbox. Measuring the motor’s resistance with an ohmmeter can help diagnose if the motor is burned out or has loose internal connections. If resistance is low but the motor does not turn, the gearbox may be jammed. The Arduino 3.3V supply is unlikely to damage the motor, but a battery could cause damage if the motor shaft was prevented from turning while powered. Proper motor driving requires a transistor or MOSFET to handle higher current loads safely.
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