To find the correct fuse(s):
1. Consult your owner's manual: This is the most reliable source. The manual will have diagrams of both fuse boxes and a legend identifying each fuse's purpose. Look for fuses related to the audio system, amplifier, or possibly even the radio.
2. Check the underhood fuse box: This box often contains larger fuses protecting higher-current circuits.
3. Check the interior fuse panel: This usually contains smaller fuses for interior accessories and electronics.
4. Look for multiple fuses: The amplifier's power might be split between multiple fuses for redundancy or different power stages.
5. Use a multimeter (if comfortable): If you can't find it in the manual, carefully check the fuses in both boxes with a multimeter to test for continuity. Always disconnect the negative battery terminal before doing this to prevent shorts. Compare the fuses visually - a blown fuse will usually be visually obvious. However, a multimeter will confirm this.
Without knowing the year and model of your Ford Expedition, I cannot give you a more precise location. Providing this information will allow for a more accurate and helpful response.
