The unit shows no sign of life when connected to power.
Safe first checks
Turn the unit off and unplug it before inspecting anything.
Try a known-working wall outlet and inspect the power cord for damage.
Check the external fuse only if the owner's or service manual identifies its location and rating.
Do not substitute a larger fuse or bypass a fuse.
Next step
If the correct fuse immediately blows again, stop testing and have a qualified technician inspect the power supply.
Bench Technician Steps
This is the model of work a qualified electronics technician follows using the exact service manual and suitable test equipment. It is not a do-it-yourself instruction to work on energized equipment.
With the equipment disconnected from mains power, inspect the cord, switch, fuse holder, transformer wiring, and power-supply boards for heat damage, corrosion, or prior repair errors.
Using the exact service documentation, check the primary path, transformer windings, and rectifier or regulator stage with appropriate deenergized tests.
If a controlled power-up is required, use suitable current-limiting equipment and monitor for abnormal current draw before making any internal live measurements.