Measure a confirmed-good unit once and keep this sheet with the board’s records. On a failed board, repeat each measurement and compare — the first divergence brackets the fault. Record your measured values here; they are not program data we can supply.

A · Power rails (DC volts)

Rail / net	Test point	Golden value (V)

Idle supply current:

B · Key-node DC signatures (powered)

Node / TP	Function	Golden value

C · Diode-mode signatures from ground (power OFF)

Black probe on ground; touch each connector/IC pin. This signature set is the fastest way to localize damage by comparison.

Pin / net	Golden reading (V)

D · Dynamic references (oscilloscope)

Signal	Golden frequency / amplitude	Notes
Main clock / osc
Reset timing
Rail ripple (AC)