World Class Quality Management for production of Silent Vehicles

A: Chasing the symptom first risks scrapping good hardware and burns test time while the root cause keeps injecting variation. The viscosity shift changes slot fill distribution and local stiffness, which moves electromagnetic excitation coupling into the housing. Freezing the process restores a known baseline so downstream NVH data means something again, and it keeps the DFMEA containment logic intact.

A: Skipping the review can let a stiffness change creep in and mask warning sounds or haptic cues, leading to a failed audit or worse, a field action. The standard forces you to check indirect safety effects of production changes, especially where silent vehicles rely on subtle feedback rather than engine noise.

A: Blaming lubrication or imbalance sends you into tear-downs that won't touch the symptom and will slip the schedule. Light-load sensitivity with clean thermal behavior points to flank form or lead error that excites under low contact stress, matching the observed narrow band without overheating.

A: Cranking torque or masking noise adds stress and can crack housings, creating rework after the witness test. Restoring the validated clamp load brings stiffness back to the correlated state so the noise path behaves as expected, while a temporary containment avoids compounding variables.