2024 SR5 voltmeter ballet

My newly acquired Tundra (10k miles) is very nice except I've noticed the voltmeter fluctuates between 12 and 15 volts pretty regularly regardless of the electric load. The needle floats up and down in an almost graceful manner. I put the Carista on and it verified that the voltage was indeed fluctuating in the same manner that the gauge indicated, probably three or four fluctuations per minute. Anyone else had this happen? I bought it over the weekend from a Toyota dealer as a Certified used car along with the remainder of the factory warranty.

 

normal

 

I think the truck uses something similar to regenerative breaking on EVs where the alternator kicks up the volts when decelerating. It also seems to unload under acceleration.

 

This. Smart alternator does the heavy charging when decelerating and light maintenance under acceleration to save gas