Which failure mode is identified by gear wear or backlash inspection?

• A. Controller failure
• B. Gear wear or backlash
• C. Sensor fault
• D. Motor stall or overheating

Answer: (B)

Focusing on gear condition and mesh accuracy, gear wear and backlash are a mechanical failure mode identified by inspecting gears. When gears wear, the teeth can become rounded, chipped, or pitted, and the clearance between mating gears (backlash) can increase. This wear or excess play means the gear train no longer transfers motion with the intended precision and can lead to sloppy motion, noise, or eventual gear failure. The inspection is specifically looking for these signs, so identifying gear wear or backlash as the failure mode is the direct, appropriate conclusion.

Other issues point to different systems. Controller failure shows up through control signals or logic errors rather than gear surface condition. Sensor fault would be indicated by faulty feedback signals. Motor stall or overheating is detected via motor temperature, current, or torque symptoms, not by examining gear wear or backlash.