What should technicians check if they have motor voltage but the door isn't functioning?

When a technician finds that there is motor voltage present but the door is not operating as expected, it's essential to check the integrity of the travel cord. The travel cord connects the door operator to the moving components and carries necessary signals for the door's operation. If there is damage, wear, or a break in the travel cord, it can prevent the motor from receiving the correct signals for movement, even though there is voltage available.

This step is crucial because even a small impairment in the travel cord can disrupt the system's operation. Therefore, ensuring that the travel cord is intact and functioning properly is a primary measure to diagnose and rectify the issue of a non-functioning door despite having voltage at the motor.