A component code names the part that was involved, not the cause. What an ultrasound service record has to carry so that someone else can code the event - and what the service side should not decide for the reporter.
A needle guide attaches to the probe, not to the console. Which is why the deciding field on a Siemens needle guide listing names a transducer: a field-by-field read, what wears on the reusable half, and what to send before you order.
A volumetric probe is either a matrix array steered in two axes or a mechanically swept array with a motor and a fluid path. Which one it is decides what fails, what the artifact looks like, and whether a repair route exists.
A probe can image perfectly and still fail its electrical safety test. The limit a leakage reading is judged against changes with the probe's applied-part class, the grounding condition and the mains voltage, and the manufacturer's own tables say so.
A dark line that stays in place as the probe moves belongs to an array element, and the picture has four possible owners. What the in-air test, an element tester and a phantom each read, what the sensitivity thresholds mean, and why two adjacent dead elements matter more than six scattered.
Pitch is the centre-to-centre distance between array elements — the sum of element width and kerf. It is not the number that sets resolution. It is the number that decides how far a beam can be steered before a second, equally strong lobe appears somewhere it was not aimed.