Buzzing sound coming from engine compartment before cranking

[Frybrid 524td]

This hasn't been an issue before but recently there has been a loud buzzing sound emanating from the engine compartment when I turn the key to the "on" position (before cranking). Could it have something to do with the glow plugs since they cycle during when the key is turned to "on"? Thanks.

[Frybrid 524td]

So it sounds like the buzzing is coming from the IP. The car runs well so I'm not sure if the buzzing is a problem... yet. The buzzing begins as soon as the key is turned on, then I can hear the glow plug relay click off but the buzzing continues until I actually crank the engine. Any ideas? Is this a precursor to something catastrophic?

[altus22]

This is normal. This is the advance solenoid on the IP.