* Under the Hood: This fuse box, often called the Power Distribution Box (PDB), contains larger fuses and relays that protect higher-amperage circuits like the starter, headlights, and ignition system. These fuses are usually blade-type fuses of varying amperages. The cover of the box usually has a diagram showing which fuse protects which circuit.
* Inside the Passenger Compartment: This fuse box, often located under the dashboard (typically near the driver's side), protects smaller circuits like power windows, interior lights, radio, and accessories. These are also usually blade-type fuses. Again, the cover will usually have a diagram.
How Fuses Work:
A fuse is a small, sacrificial device containing a thin wire that melts and breaks the circuit when too much current flows through it. This prevents damage to more expensive components like wiring harnesses, computers, and electrical motors. If a fuse blows (melts), it needs to be replaced with a fuse of the *same amperage rating*. Using a higher amperage fuse is dangerous and can cause a fire.
Understanding the Fuse Box Diagrams:
The diagrams on the fuse box covers usually show:
* Fuse Number: A numerical identifier for each fuse.
* Amperage Rating: The maximum current (in amps) the fuse can handle before blowing.
* Circuit Protected: A description of the electrical component or system the fuse protects (e.g., headlights, power windows, radio).
Troubleshooting:
If a particular electrical component stops working, check the corresponding fuse in the appropriate fuse box. A blown fuse will appear visibly broken – the wire inside will be melted or separated.
Important Notes:
* Always turn off the ignition before checking or replacing fuses.
* Never replace a blown fuse with a higher amperage fuse. This is a serious fire hazard. If a fuse blows repeatedly, there's likely a short circuit in the wiring that needs professional attention.
* Consult your owner's manual: The owner's manual for your 1998 Ford Expedition XLT is the best resource for accurate fuse box diagrams and descriptions. It will provide the most detailed and reliable information specific to your vehicle.
Without access to your specific owner's manual, I cannot provide the exact location and descriptions of each fuse in your vehicle. Refer to your owner's manual for complete and accurate fuse information.
