1991 740 2WD non turbo.
Fuel pumps won't come on when I turn the ignition to the start position. I've pulled the relay and fuse block out to check the fuel relay. All fuses test good continuity underneath the fuse block ruling that out.
I removed the pump relay cover and determined that the contacts are not stuck, are clean and the relay coils are good.
With the relay cover off I can press the pump contact closed to run the pumps to start and run the engine.
The pump relay appears to send the Normally Off position somewhere. I'm assuming that it is to a high fuel pressure control that cycles the pump on/off while driving.
I don't have the electrical schemes for this car, so am quite hindered
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