Xenon Light Issues

[Stenik]

Hello All,

Hopefully somebody on here can help. I have recently purchased a 2002 3.0 petrol X5 Sport.

I am having problems with the head lights which seems to be intermittent problem. When I turn on the low beam ( Xenon units ), sometimes the passenger unit will illuminate, sometime the drivers unit will illuminate and then sometimes neither will come on. Both units eventually turn on after turning the headlight switch back to sidelights and back to headlights. I get a warning up on the OBC saying "Check Low beam". Once they are both on, they stay on and they will turn on and off no problem and relight. Sidelights and main beam are ok. I am aware these are separate units.

Does anyone have any idea. I have browsed through all 53 pages and there is a various topics that possibly point to the battery condition?

I also have the "Active Suspension - Inactive" error, but I have been told this is supposedly a sensor fault.... I won't know for sure until I get the error codes read.

Any thoughts would be very welcome.  Wishing everyone a very Happy New Year.

All the Best.

Steven

[X5Sport]

First......

Second.....is your battery fully charged?  If not, charge it from the under bonnet points.

It is possible that the Light Control Module (LCM) may be faulty, but check for good battery connections in the battery compartment under the boot floor.

Richard

[Steamyrotter]

HI

Could be the ballast on the way out also..
The inrush from the ballasts can cause rogue warnings to come up especially if the battery level is slightly iffy...

Also worth a check (if you can) is that the PWM signal to the dip beam is disabled.....
this is something in the LCM coding.  It is part of the ulb failure and headlight dimming functions...
Apparently you can set any of the front lights (bar fog) as DRL and the PWM function will dim them to a set level.
If the LCM is outputting a PWM signal then it will set up harmonics in the electrical system  (as the ballasts are inductive loads) that can cause major headaches.


no prizes for guessing how i know that??

[Stenik]

Hi Guys and thanks for the replies. I will check the battery condition and connections initially.

After that I take it is onto the headlight units. With both Ballasts possibly faulty, I won't be able to swap them with each other to identify a problem. Apologies for my ignorance, but what is a PWM signal and how would I check it? I do not have DRL's active. I am used to working on cars, but a lot of this technology is new to me. Any other suggestions for me to try?

This is my 3rd X5, ( Previously a 3.0D Sport and then a 3.0 D Twin Turbo ) fortunately the last 2 were company cars and any issues and I whisked the vehicle off to BMW. No I own one, I would like to resolve the issues myself and naturally for as little expense as possible.

I also have and OBD Wifi Link that I used on my last car that paired up tot an IPAD to diagnose faults and read error codes. Do you know if this will work on the X5?

Sorry if I am being a pain.

[Steamyrotter]

PWM  = Pulse Width Modulation
It is a high frequency pulse of the supply which can be used for dimming lights.

Easiest way to check if it is enabled is to connect a relay across the power supply wires.
If it is enabled the relay will vibrate and chatter madly...

If it is on you will need to get hold of someone with appropriate software to be able to turn it off

[Stenik]

Bulbs replaced today. Still not right. New ballast units ordered. Fingers crossed this will solve it. Next step is Halogen conversion. I have now got an Xenon issue on my Audi RS4. Are these headlights really worth it!!!!! Loosing sleep over Xenon lights.....

[X5Sport]

I've had HID lights on 5 different cars and never had an issue so far.  I much prefer HID to filament, but like anything else as it gets old there can be problems.

Richard