To find the relevant relays and components, you'd need to:
1. Consult a wiring diagram: This is the most accurate way to pinpoint the relays associated with the air suspension compressor and other components. A wiring diagram specific to your Expedition's year and model is essential. You can usually find these online through repair manuals (like those from Haynes or Chilton) or from Ford directly (often requiring a subscription or dealer visit).
2. Locate the Power Distribution Box (PDB) or fuse box: Many relays associated with vehicle systems are found in these boxes. The location varies depending on your Expedition's year. The owner's manual is a good place to find this. Once located, carefully inspect the relays for labels indicating their function. However, identifying the air suspension relays just by labeling is unlikely without a wiring diagram.
3. Use a scan tool: A professional-grade scan tool can often read diagnostic trouble codes (DTCs) related to the air suspension system. These codes can narrow down the problem area and potentially point to a faulty relay or module.
In short, there's no single "air suspension relay switch" to find. Troubleshooting requires a deeper understanding of the system's electrical architecture, making a wiring diagram and potentially a scan tool necessary.
