XENON BALLAST REPLACEMENT HELP - Any Experience?

Hi,
I had water infiltrate my right headlamp area (645Ci). Light went out and of course headlamp error on. Diagnosis confirms:
Bulb OK
Igniter OK
High beam OK
Halo OK
Given that, I'm told it's 90% sure the ballast is bad which is less that a $100 part. As I understand though, I have to drop the bumper to get to the ballast and replace this? I have some other reasons for wanting to drop the bumper also so I think I'll do it. Anyone have experience with this? Any suggestions on where I can get instructions?
Thanks,
Scott

Drop the bumper. Ballast you mean xenon module right?. Repair instruction in tis or alldata

Sent from my Nexus 7 using Bimmer App

Hi MINI+BMWtek,

THANK YOU! TIS is a FANTASTIC DIY resource!

Yes, as I understand it, the "ballast" is also the "control module". Looks like removing the bumper is not that difficult.
Sounds like you're experienced in this - any advise? Would you agree with the above diagnosis - that it must be the "control module"?

Thanks again,

Scott

xenon modules due tend to get water ingress very easy,make sure your order the right part since the smc ecu is very similar. Removing headlight is needed to access ecu,some BMW you can snake out the xenon w/o removing headlight but i dont remember for E63 I usually need to remove inner liner from what i see i make the choise to r/i headlight. Starting from E65 r/i bumper is ness. To r/i headlights