I have some good news and some bad news ...
The good:
I found 5_FACH_TIPPBLINKEN under 3000 HMI in Headunit Expert Mode. I changed it to "aktiv", HU rebooted, then I exited BimmerCode, restarted car and went back into BimmerCode to confirm the setting. Thanks to maaii11, Takabo and kavatski.
The bad:
It still only blinks 3 times!
