hi all,
may i just introduce myself briefly - I'm Nam and I'm a happy Z4 owner coming from Germany. I was very impressed when I found this article because I was very keen to upgrade my prefacelift z4 with the new tail lights.
without your post i haven't tacled this project because on the german z4 pages i just read several times that you need the light control module from facelift which is very expensive.
just to contribute. i found elegant solutions for your issues:
1. the tail lights and break light is on
well, to prevent the "t" effect, you just have to code your light control module - in german the code is:
BREMSLICHT_ALS_STANDLICHT
nicht_aktiv
this means the breaklight should not longer work as your side markers and then they are off. everything works as intended (break, tail light..)
2. flickering of taillight / 6V issue
well, you took the power of the light of your plate sign - you can also program your light control module as follows:
PWM_ANSTEUERUNG_SL_RE_HI
wert_01
PWM_ANSTEUERUNG_SL_LI_HI
wert_01
this gives 12v to the tail lights without further modications.
this works out perfectly with my 2003 Z4 - hence no really need to buy the new light control module.
3. bulbs in the cockpit / dashboard
just deactive the checkcontrols and everything is fine.
this week, i bring my new bumper to the body shop and then i can finalize my project
thanks for your great post!
cheers Nam