My 06 pre lci 525i has faded and scratched headlights. I want to know if I can change these to Bi xennon or if I should just swap them out with original units to keep the car in immaculate orginal condition.

As far as you can or not? Yes, in fact I did pre-LCI -> LCI Bi-Xenon.

But not w/o work ... for a start Bi-Xenon at least require additional wire in the plug that is not present in the Halogen wiring loom that you have to add. After that since your car DNA was born w/ Halogen so iDrive will do it checks knowing you have Halogen which is a different way w/ checking Bi-Xenon setup so to avoid warning(s)/error(s) you have to decide how to deal w/ that, the right way is coding your car from Halogen -> Bi-Xenon if not you have to install various error canceler otherwise the Bi-Xenon will strobe then the parking light will give you warning ('cuz the AE on Bi-Xenon uses single bulb on each headlight while Halogen got 2 and their wattage are diiferent) so you have to add somethin' like resistor.

Additional splice on the wiring for the Xenon hi-beam may also needed ... so do an extensive search as some member did Halogen -> Xenon coversion both the 'factory' and/or 'hack' way.

GL!

hi, i have bought my 525d with the LCI headlights. i got parking light error on my iDrive. I have been told to get 5w Resistors and add them.. but i dnt know were and how to do this please can you help. Cheers

Dont know the rules in Australia, but here you can of cause change from Hologen lamps to Xenon but you need to do the following to make the car legal.

1) Headlight washers
2) autoleveling of the xenon, equals a sensor in the front right wheelarc and one in the left rear wheelarc.

And as they say a change in wires and a new lightmodule (LMA)

Best regards

Holtz