Fluctuating Voltage

[Thor2j]

Need some help.
Have a 2019 with only 40k.

Started noticing on my voltage gauge , that once the truck warmed up, the voltage would react directly with gas pedal. If you are driving constant speed or accelerating it is 12.5-12.6 volts. When you lift off the pedal it shoots to 14.8-14.9.
Bought new battery , didn't help. Have platinum warranty , took to dealer. Reset BCM, worked until half way home. Took it back. They replaced BCM, worked for about 60 miles then back. I'm convinced it's the alternator. It's going back to Ford tomorrow. Problem is BCM wasn't covered under warranty and it takes weeks to get truck looked at.
Anyone have any ideas??

 

[FordTechOne]

That’s normal operation of the charging system. It reduces charging voltage under load and then increases it when coasting. The strategy reduces parasitic drag, which improves fuel economy and engine performance.

If there is an actual charging system issue then there will be a warning message/indicator with associated DTCs.

 

[Thor2j]

That’s normal operation of the charging system. It reduces charging voltage under load and then increases it when coasting. The strategy reduces parasitic drag, which improves fuel economy and engine performance.

If there is an actual charging system issue then there will be a warning message/indicator with associated DTCs.

Thanks.
Crazy ford doesn't know this.

 

[Hal993]

That’s normal operation of the charging system. It reduces charging voltage under load and then increases it when coasting. The strategy reduces parasitic drag, which improves fuel economy and engine performance.

If there is an actual charging system issue then there will be a warning message/indicator with associated DTCs.

Is that to say that seeing a constant voltage as low as 12.0 at times ... for a long time is normal?

I don't believe I like BMS. I see anywhere from 14.5 to 13.5 to 12.0 ... aaaand at night, my blinker doesn't blink in a straight pattern.

Brand new Interstate H7 (OEM spec) that was charged before install and BMS was reset.

 

[FordTechOne]

Is that to say that seeing a constant voltage as low as 12.0 at times ... for a long time is normal?

I don't believe I like BMS. I see anywhere from 14.5 to 13.5 to 12.0 ... aaaand at night, my blinker doesn't blink in a straight pattern.

Brand new Interstate H7 (OEM spec) that was charged before install and BMS was reset.

Yes. It’s normal. The battery charges based on demand.