At startup? Mine has always “clicked “ at about 2000 rpm after startup. Alt light goes off with the click. 
Jeff
85 Westfalia GL
Sent from my iPhone

> On Jan 28, 2024, at 1:25 PM, Markus Benne <mbenne@m-bass.com> wrote:
> 
> I've noticed a behavior where the alternator will not charge the battery (and no alternator light is on) until I hit a high rpm.    Then I hear a relay click and the voltage jumps to 13.4ish volts and the battery is charging normally.
> My usual suspects are bad ground and/or a bad relay.
> Someone hit this before?
> Thanks,...Markus