"Nothing at the fuel pump relay. I pulled the cover, and it looks fine - not corroded or anything - all contacts move easily. Left the cover off, plugged it back in, turned motor over - watched it closely - nothing."

• Are you saying that neither of those two relays under the cover got energized? If so, that points back to the 25 Amp fuse. Check for voltage on the red wire coming into the relay plug. You can leave it connected and "back-probe" with meter lead or (better yet) a 12V test light. The voltage should always be there, and should not change much when the Key is turned on (either before or during cranking).

The Main relay should close as soon as the key is turned on, to power up the ECU and AMM. It also powers the Fuel relay's + side. But the Fuel relay doesn't energize until the ECU senses timing pulses from the Ignition CU during cranking. Only then does the ECU energize the the Fuel relay by grounding its coil (blue-green wire).

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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.