Pattern to record: Power is present but the Mac remains black or repeatedly enters recovery behaviour.

Use the correct Mac power design

Intel MacBooks span MagSafe and USB-C charging designs. Match the diagnostic procedure to the model and connector; a USB-C negotiation test is irrelevant to a MagSafe-only machine. Startup firmware is incomplete or corrupted and normal boot cannot begin.

Power and data precautions

Disconnect internal battery power before handling board connectors. A restore can erase data, so the selected recovery action must be understood first.

Model-specific checks

1. Separate SMC state, memory or storage symptoms from missing power rails using model-specific tests.
2. Identify the Mac generation and follow its documented recovery procedure after confirming stable power; revive/restore procedures apply only to supported Apple-silicon or T2 models.

Repair and startup verification

If the checks support this cause, use the supported recovery action for that model, distinguishing a data-preserving revive from an erasing restore where those options exist. Verification should cover cold start, charger and battery operation, sleep, wake, restart and thermal response.

Reference: Apple support guidance.

For an assessment of your Intel MacBook, contact AEPC in Burswood or call 027 908 8880. Provide the model and the conditions that reproduce this problem. Workshop visits are by appointment.