There are two relays in the circuit that powers the fuel pump. Relay 2/32 is the one you've found in the box underhood and is called the Fuel System Main Relay. It feeds power to the actual fuel pump relay through fuse 11B/4. That fuse is located in that underhood relay/fuse box, and is the 4th one from the rear of the car in the row closest to the relays. Check it. The relay also powers the ignition system, and a lot of other components.

The fuel pump relay 2/23 is located in the panel at the left end of the dashboard and is the middle one of the three relays in there. Open the driver's door to see the panel cover.

If you pull that relay and probe the slot with your voltmeter where its "30" terminal plugs in you should see 12V when you crank the engine. If so, relay 2/32 is working, and fuse 11B/4 is OK.

To check for 12V supplied by 2/23 to the pump there is a small connector in the trunk (probably under carpet and panels at left side) which has only four wires, 2 Black and 2 Pink. The pink is the 12V feed from relay 2/23, so probe it with the voltmeter while cranking.

Of course a fuel pressure gauge could sidestep all the electrical investigation, but they're hard to find outside of a pro shop.
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Bob: Son's XC70, my 83 244DL, 89 745 (Chev LT-1 V8), 98 S90 (recently sold) and 2010 XC60. Also '77 MGB and four old motorcycles