2020 Mercury 250 ProXS V8 4 Stroke Noise - Help

[ChampionDon]

2020 Mercury 250 ProXS V8 4 Stroke
Model Number 1250033A
Serial Number 2B736500
250LPXS

It was making a noise when I went into the garage. Unplugged the charger and it was still making it. So I removed the fuse for the clean power harness and it stopped. Checked the fuse and all was good. Put the fuse back in and it started making the same noise a tad later like every 3 seconds. So I removed the fuse to deal with it the next evening.

So I pulled the boat out and removed the cowling, put the fuse back in and bumped the trim button and I heard it make the noise and then it never made the noise again. I began to replace the water separator fuel filter and then primed it for 5 seconds per the instructions, once primed I turned the key and let her run for 3 seconds, then turned it off. When I turned it off I heard the exact same noise that it made the previous day, but it only did it once right after turning the key off. So I let it set for about 2 hours checking on it regularly to see it would make the noise like it did the day before, it never did.

Then I turned the key on again , heard the fuel pump prime and when if stopped I then turned it off, did not fire the engine. It was then I heard the exact same noise that it made repeatedly the day before. So I repeated the previous steps and heard it again. Here is a recording of it. It starts out like a humming noise, then clicks. The noise it makes after turning off the key is what it was making the previous day continuously about every 3 seconds until I pulled the clean power fuse. Anyone know what that noise is coming from on the last part of the video? Any idea as to why it may have been doing it the day before continuously?

[ChampionDon]

Update, so I called my buddy who also has the same engine and he preformed the same function that I did and it made the same noise...so that is normal. He also bumped the trim button up and then down and it made the same noise. I did not test the trim up and down button on mine, but that would explain why I heard it when I bumped the trim the first time on mine as well. So if it is normal then why was it doing it constantly every 3 seconds? It is like something is open and closing when power is provided to the section of the engine where the + and - run to on the engine.

[ChampionDon]

Update was told to clean and ensure that all the cables to the cranking battery cables are tight. Mercury recommends 15lbs of torque on the nuts.

[EuropeanAM]

Update was told to clean and ensure that all the cables to the cranking battery cables are tight. Mercury recommends 15lbs of torque on the nuts.

+1

Also- there is a strategy for PCM/MPR Wake-up with trim switch activation. This allows you to raise and lower the engine without having to go turn the key "on" first.

After remaining idle, the MPR and PCM will go back to sleep (and there is a discernible clicking sound during the wake-up and shut-down). Should not be a continuous clicking, however.