Originally Posted by Schwartz540i
I have read that installing a used rain sensor requires reprogramming by BMW. Can anyone confirm if this is true?
Not sure, but I don't think you need to reprogram for a same-unit swap out. I seem to have stumbled across others on-line doing the swap-out for failed modules w/o problems. You DO need a reprogramming if removing the rain sensor altogether to get normal interval wiping back. You probably also need to reprogram if adding a rain sensor to a vehicle that was not originally equipped with one. Basically, whatever module is controlling the wipers needs to know if it's there or not.
As a compooter enginear that's tinkered with interfacing to the BMW's electronics, I doubt that they'd need to plug it in to DIS to re-code a swapout. The module is stamped with a firmware rev, so that comes with the module. I am speculating though. I know reprogramming is needed for the IKE (instrument cluster) and LCM (light control module), and DME replacement, but that's cuz those devices also back-up the mileage and store the VIN.
Let me know how it goes.