* Under the hood in the fuse box: This is the most common location. The fuse box is often located near the battery, sometimes under a cover. Look for a diagram on the inside of the fuse box lid to identify the relay. The relay itself might be labeled, or you might need to use a wiring diagram to trace it.
* Under the dash: Less common, but possible. This location would usually be in the area of the other relays and fuses inside the vehicle's cabin.
* In the Power Distribution Center (PDC): Some vehicles have a PDC, which is a more substantial fuse/relay center, often located near the battery but not always under the hood.
To find it reliably:
1. Consult your owner's manual: This is the best starting point. It should have a diagram of the fuse and relay boxes showing the location of the fuel pump relay.
2. Use a wiring diagram: You can find wiring diagrams online (often on forums dedicated to GMC Vanduras) or purchase a repair manual specific to your vehicle's year and model. These diagrams will show you the relay's location and the circuit it's involved in. This is often the best method if the owner's manual doesn't provide enough detail.
3. Use a multimeter (with caution): You can use a multimeter to test for power and continuity at various relays to locate the one controlling the fuel pump. Exercise extreme caution when working with automotive electrical systems. Incorrectly testing or connecting a multimeter could damage your vehicle's electrical system or cause injury.
Remember safety first! Disconnect the negative battery terminal before working with any electrical components.
