In cockpit electrical fault troubleshooting, which step typically follows verifying power sources?

• A. Follow QRH steps.
• B. Isolate the symptom.
• C. Check fuse/bus status.
• D. Replace the entire electrical system.

Answer: (C)

After you’ve confirmed the power sources are providing the correct voltage, the next step is to check fuse and bus statuses. Fuses and bus bars are the distribution path for electrical power; a fuse can blow or a bus can trip, cutting power to multiple circuits even when the sources themselves are healthy. Inspecting these areas quickly reveals whether the fault lies in the distribution path rather than the sources, guiding you to the correct next actions—whether that means continuing with QRH procedures or isolating the symptom. Replacing the entire electrical system isn’t a normal next move and wouldn’t match the systematic troubleshooting approach.