No power to cool fuel pump.
 

Starting a new thread as the other one is 6 years old. 1997 Gen VI 502 mag MPI. It sat for 2 months at the marina and fired up no problem to bring home. On the voyage home, Stbd engine died and I restarted it no problem. Got home and tried to flush it, no power to fuel pump. Things I have tried: swapped fuel pups, fuel relays, ECM's, ignition switches, good voltage, bench tested the fuel pump. In the other thread it mentions a pink wire going to the fuel relay, I unwrapped the wire to the point it makes the bend forward towards the ECU. Im out of ideas. I can hear the relay clicking when I turn the key to ON but no buzz. I can recycle the key and got it to wake up on about the 20th try....then nothing again. Good battery voltage and it cranks fine. Im thinking a short or bad ground. Could it be something stupid like a bad connector to a Tach or Volt gauge? Thanks.

Check the cannon plug(main harness plug on motor, usually has hose clamp, or zip tie.)
Had a new tech struggling to diagnose no power to fuel pump.
Told him to wiggle cannon plug. Pump starts. Just a minor amount of corrosion on a pin in plug. Good luck...

I'm with you with these comments and also one other not mentioned
Key turns ON and MPR (Main Power Relay) energizes, gauges light up - good

The fuel pump turns ON by the ECM applying a ground to the FP relay. My first guess is the ECM is applying a ground but the FP relay is not energizing. You can swap the MPR with the FP relay, and if the FP relay is bad then gauges will not turn ON

Ill pull it and inspect when i get home. thanks!

Is the MPR sitting right next to the fuel pump relay? If so, I can swap them to see if there is any differences. I did mention that I get a click on the fuel pump relay so in my head its bueno (let me know if my logic is faulty...electron isnt my forte). I also swapped the fuel pump relay with the good engine and same result. Back to your 'good' comment...yes, I get power to the gauges on that side and the three beeps when I turn the key to ON. I didnt mention that before. My neighbor is a retired electrician......Might need to bribe him over on this one.

Like Velocity mentioned....I have not pulled the main cannon plug yet.

Yes, and swapping them is a good

Easy enough! Thanks.

It was the Main Power relay. All fixed and thanks guys.

All electrical problems should be solved with a volt meter, not parts changing but you gotta know about electricity.
Good to hear its solved