Use the assignment chart by matching each cavity number to the exact circuit before replacing any blade link. For cabin-side checks, verify positions tied to audio, climate control, interior lighting, power outlets, central locking, wipers, and the instrument cluster. For the engine-bay section, inspect slots serving cooling fans, ABS, horn, starter feed, and front lighting. This saves time and prevents swapping a healthy insert while the real fault remains in a relay, wiring branch, or load device.
Choose a puller, read the amperage marking on the plastic body, and replace only with the same rating: 5A, 7.5A, 10A, 15A, 20A, 25A, 30A, or 40A, depending on the protected line. A melted strip usually points to overload or a short to ground, not just a worn part. If the new insert fails right after installation, stop there and test the circuit with a multimeter; repeated replacement can damage connectors and control modules.
For fast troubleshooting, separate symptoms by area. No cabin accessories usually means checking the interior panel first. No cooling fan, no horn, or no charging-related feed sends attention to the engine-bay unit. If one side of the car loses several unrelated functions at once, inspect the main supply links and shared grounds before chasing single consumers. Keep the cavity map next to the vehicle manual and confirm each label against the panel cover, because trim level and installed options can change slot usage.
Passenger-Compartment and Engine-Bay Power Layout for the Compact Hatch/Sedan
Check the cabin panel first: it sits behind the glove compartment on the passenger side, and the map you need is printed on the rear cover. For the 2.0L version, the slot commonly tied to the power outlet is 61 at 20A, while the audio unit is typically protected by 67 at 15A. Wipers usually run through position 56 at 30A, and the central locking circuit is often assigned to 65 at 20A. Pull the key, switch off every load, and use the plastic extractor clipped inside the cover; swapping in a higher amperage insert risks melting the harness rather than solving the fault.
Under-hood panel layout
The engine-bay distribution unit is mounted near the battery. Cooling fan control commonly uses a high-current cartridge, ABS support is usually on a separate heavy line, and the heated rear glass often sits on its own 40A path. If the radiator fan, horn, or washer pump stop at the same time, inspect this compartment before checking relays in the passenger area. Match cavity numbers to the lid chart, verify continuity with a multimeter, and replace only with the same color-coded rating: tan 5A, brown 7.5A, red 10A, blue 15A, yellow 20A, clear 25A, green 30A.
Where to Find the Interior and Engine Bay Fuse Boxes on a Ford Focus
Open the front passenger door and check the trim panel at the lower edge of the dashboard, beside the glove compartment area; behind that cover sits the cabin power-distribution panel.
Use a plastic trim tool or your fingers at the small notch in the panel edge, then pull the cover straight out without twisting it. A flashlight helps because the mounting points and circuit labels are low and partly hidden by the dash contour. If access feels tight, slide the passenger seat back first.
Under the hood, the main electrical center is placed on the left side of the engine compartment, close to the battery. Release the bonnet, secure it with the prop or struts, then look behind the headlamp area on the driver side. The lid usually has retaining clips that must be pressed before lifting. Keep the cover aligned as you remove it so the sealing lip is not bent.
For the passenger-compartment panel, do not search under the steering column first; on this model, that is the wrong place for most cabin circuits. The interior unit is offset toward the right side of the dash, which is why many owners miss it during a quick inspection.
If you are checking a blown link, switch off ignition, lights, audio system, and climate controls before touching anything. Pull the suspect part straight out with the small extractor stored in the under-hood panel, compare the metal strip inside, and replace it only with the same amperage rating. A higher value can damage wiring, modules, or connectors.
After reinstalling each cover, press along all edges until every clip seats flush. A loose interior panel can rattle over bumps, while a poorly closed engine-compartment lid may let in moisture and dirt. If the printed chart on the cover is missing or unreadable, match the cavity numbers to a service manual or the owner handbook for the exact circuit layout.