* Inside the fuse box (under the dash): This is the most common location. The fuse box is typically located under the dashboard, often on the driver's side. Look for a relay that's labeled, or consult your owner's manual or a wiring diagram. The relay itself might not be labeled "fuel pump," but the wiring diagram will show you which one it is.
* In the engine compartment fuse box (less common): Some models might have a secondary fuse box in the engine compartment. Check this location as well, if you don't find it under the dash.
To find it definitively:
1. Consult your owner's manual: This is the best first step. The manual should have a diagram showing the fuse and relay locations.
2. Use a wiring diagram: A wiring diagram specific to your 1989 VW Fox will pinpoint the relay's location and associated wiring. You can often find these online through VW enthusiast forums or parts websites.
3. Use a multimeter: If you're comfortable with basic electrical work, you can use a multimeter to test the relays in the fuse boxes to find the one that controls the fuel pump. (Be cautious when working with car electronics).
Without the specific model and trim level of your 1989 VW Fox, it's impossible to give a more precise location. Always refer to your owner's manual or a wiring diagram for the most accurate information.