P0621-15 alternator Ducato 2017

[alessioblaupunkt]

P0621-15 alternator signal - short to battery or ground

There is no short to battery
There is no short to ground
The LIN wire from alternator to the ecu has continuity.

The signal coming out from the Valeo alternator looks like a DC voltage with some small ripple on top.
Key off: 11.97 V from the LIN that goes out to the alternator.

Problem is when you start the engine, alternator will not charge untill you hit throttle pedal.
If you hit throttle pedal the alternator immediately produces 13.50V

For self curiosity:
If you start the engine and leave the Duki on, in my case battery voltage 12.25V,
with all the optional OFF, half an hour later battery voltage is 11.55V with engine running.
Again just hit rapidly the throttle pedal and here there are 13.50V for the battery.

The error is active, if you delete it will reappear two seconds later.

Tried to change $$$ alternator, no help.
I suspect of bad ecu, but I will not risk $$$$ only because it will not charge.

[Meat-Head]

Intelligent battery terminal

[alessioblaupunkt]

No. Has no IBS, no s&s, no SCR, nothing.
Just a regular but modern Ducato.
Btw van is in street now, will see what happen in the next days.