Red arrow in energy monitor

I think I, at least, would need more info. I never use the energy monitor. It has arrows that flash & move around, but there are no buzzers associated with the energy monitor. Some things that will trigger a buzzer are:
Blind Spot Monitor (BSM)

• Brake system
• Downshifting
• Lane departure alert
• Open door
• Open moon roof
• Parking assist sensors
• Pre-collision warning
• Radar cruise control
• Seat belt reminder

 

What were you doing at the time this occurred? Was the car READY or just powering up? Were you shifting out of Park? Was the door open or closed? Was the car moving? The car will warn if you get things out of sync: doors closed, brake pressed, power button pushed, READY illuminated and one "ding", shift out of Park with brake still depressed. Also, if you open a door with car not in Park, it will alert you.

 

Are you sure it wasn't this? ^

Normally, if there's a beep, a message will take over the MID and you won't even see the energy monitor for a few seconds.

Then again, your AWD may have features the 2WD does not have.

 

Yes, just like the manual says, from the battery is yellow. From the ENGINE to the wheels is red.