Xenon - high beam OK, low beam not working

[E53inLA]

Hoping someone can shed some light on this problem...

Drivers side low beam stopped working. My mobile mechanic & I have tried:

1) New Xenon bulbs
2) New amber turn bulbs (as long as the assembly was out, we figure it prudent)
3) swapping the ballast, left to right, and a used one I got on EBay.

At one point today, when we temporarily reinserted the assembly, after swapping the ballasts, both low beams were working. Since we didn't reinstall the plastic retaining cage for the test, we had to remove the assembly, reinstall the cage, reinstall the headlight assembly.

After putting it all back together:

Passenger side works fine. Low beam is on. High beam works on both positions, turn signal works.

Driver side:

Low beam not working
High beam works on the pull-to-driver position, but not on push-to-dashboard position.
Turn signal working

Any help/suggestions greatly appreciated. (and I did search first, but didn't find anything similar)

[TerminatorX5]

strange... you say both sides were working at one point when you "bench" tested the left light?.. and the problem did not move when you changed the ballasts, the bulbs?... the LCM has ability to "shunt" faulty circuit to avoid further issues and bypass the light... on the other hand, if the conditions are right, the light should come back...

do you have the ability to read the error codes from the LCM? it will list the error codes and their description if you use the BMW software to pull the codes... you might find the explanation there, like check driver's xenon not-plausible, error occurred 5 times, or 20 times or whatever...

did your left fog light come on too? there is a fail-safe protocol, when the fog lights come on if the main lights are not working...

[E53inLA]

Yes, at one point both low beams came on. I don't recall if we tested high beams, but we did test turn signals. That was when we were swapping ballasts to try and isolate if that was the problem. Everything looked good, so we pulled the assemblies, reinstalled the cages under the ballasts and put it all back together. Then it was getting dark (doing this in my driveway) so we ran short of time to continue.

After we put it back together, I tested high beams on both positions. That's what really has us stumped, as juice is getting to the Xenon bulb, but only in the one position.

[TerminatorX5]

your explanation needs some more explanation...

the high beams on standard US spec'd facelifted E53 operate as follows:

engine is running
when the lights are on, the amber corners are on
the low beams xenons are on
when you flash to pass, the inner halogen highbeams are coming on
if your front fog lights are on, they turn off while the inner highbeams are on for flash to pass
when the highbeams are engaged in regular fashion, the mechanical metal shield inside the xenon light assemblies are moved with a solenoid thus releasing the full, unobstructed xenon beam.

during this process, the inner halogen highbeams do NOT illuminate.
the xenon light does not get additional power, nor it ignites anything in addition to regularly lit xenon light - just a metal shield removed from the path of light.

with the coding, it is possible to keep the inner halogen highbeams on while the xenon highbeams are engaged. also, with coding, it is possible to keep the front fog light on, while the highbeams are engaged... but this is a different story altogether

this operational description is different from what i picture from your description - it seems that in your case, the xenon light is dark, but when you engage the highbeam, the power is supplied to the ballast and the xenon light ignites... Do we get correct picture?

also, we are running off an assumption that you have facelifted model...

please indicate the car specifics, as the LCM has had changed and had different programming over the production years...

[E53inLA]

Date of manufacture from the tag is 06/05

I am original owner. IIRC the only option we got was Sport Package, but I may be mistaken. I'm a little hesitant to post VIN publically, but could PM it to you. Car was purchased in California, and been in Los Angeles except for a couple trips to SF and Arizona.

No aftermarket parts to headlights were added.

Let me know other specifics you want. Not sure what "facelifted" means, but I could post a photo if that helps.

Thank you.

[TerminatorX5]

you can PM me the last 7 digits of the VIN if you wish...

meanwhile, give me a description of what is happening with your lights.

to establish the baseline -

outer lights with xenons - are bi-xenons, can be operated as low beam, and as high beam together with low beam
inner lights are halogens, can only be used for the highbeams and daytime running lights at reduced intensity
front fog lights, can be turned on when the light switch is in auto mode or in parking or in lights mode
halos, corona lights, angel eyes - the circular lights around the perimeter of low and highbeams, sometimes referred to as "parking lights"

now, i want to know, from the moment you walk up to your car, start the engine... in what position your light switch (S8) and fog light switch, and the high beam stalk... and what results you have with each position...

something like this:

- light switch in auto mode
- turned engine on, left and right low beams came on, fog light switch off, fog lights off, high beam stalk off, high beams off
- turned fog lights on, left and right light came on...

something like that...

can you document this and post it?

[TerminatorX5]

Vehicle information
Type
Value
VIN 5UXFA13585LX*****
Type code FA13
Type X5 3.0I (USA)
E series E53 ()
Series X
Type GEFZG
Steering LL
Doors 5
Engine M54
Displacement 3.00
Power 170
Drive ALLR
Transmission AUT
Colour BLACK SAPPHIRE METALLIC (475)
Upholstery LEDER DAKOTA/SCHWARZ (LCSW)
Prod.date 2005-06-03
Close Options
Code
Description (interface)
Description (EPC)
S1CAA SELEKTION COP RELEVANTER FAHRZEUGE Selection of COP relevant vehicles
S205A AUTOMATIC GETRIEBE Automatic transmission
S226A SPORTLICHE FAHRWERKSABSTIMMUNG Sports suspension settings
S255A SPORT-LEDERLENKRAD Sports leather steering wheel
S2LBA LM RAEDER Y-SPEICHE 131 BMW LA wheel Y-spoke 131
S321A EXTERIEURUMFAENGE IN WAGENFARBE Exterior parts in vehicle color
P330A SPORTPAKET Sports package
S386A DACHRELING Roof railing
S402A PANORAMA GLASDACH Electric panoramic roof
S417A SONNENSCHUTZROLLO HINTERE TUERSCH. Roller sun vizor, rear door
S438A EDELHOLZAUSFUEHRUNG Fine wood trim
S441A RAUCHERPAKET Smoker package
S442A GETRAENKEHALTER Cup holder
S459A SITZVERSTELLUNG, ELEKTR.MIT MEMORY Seat adjuster, electric, with memory
S461A SITZLEHNENVERSTELLUNG IM FOND,ELEK. Electric seat backrest adjustment, rear
Code
Description (interface)
Description (EPC)
S481A SPORTSITZE FUER FAHRER/BEIFAHRER Sports seat
S488A LORDOSENSTUETZE FAHRER/BEIFAHRER Lumbar support, driver and passenger
S521A REGENSENSOR Rain sensor
S522A XENON-LICHT Xenon Light
S524A ADAPTIVES KURVENLICHT Adaptive Headlights
S533A FOND-KLIMATISIERUNG Air conditioning, rear
S534A KLIMAAUTOMATIK Automatic air conditioning
S609A NAVIGATIONSSYSTEM PROFESSIONAL Navigation system Professional
S639A KOMPLETTVORB. HANDY USA/CDN Preparation f mobile phone cpl. USA/CDN
S676A HIFI LAUTSPRECHERSYSTEM HiFi speaker system
S761A INDIVIDUAL SONNENSCHUTZVERGLASUNG Individual sunshade glazing
S775A INDIVIDUAL DACHHIMMEL ANTHRAZIT Headlining anthracite
S8SPA COP STEUERUNG Control unit COP
S926A ERSATZRAD Spare wheel
S945A BERUECKSICHTIGUNG PREISABHAENGK. Dummy-SALAPA
Close Standard equipment
Code
Description (interface)
Description (EPC)
S249A MULTIFUNKTION FUER LENKRAD Multifunction f steering wheel
S302A ALARMANLAGE Alarm system
S354A GRUENKEIL-FRONTSCHEIBE Green windscreen, green shade band
S645A RADIO-STEUERUNG US BMW US Radio
S692A CD WECHSLER I-BUS VORBEREITUNG Preparation, BMW 6-CD changer I-bus
S785A WEISSE BLINKLEUCHTEN White direction indicator lights
S845A AKUSTISCHE GURTWARNUNG Acoustic belt warning
S853A SPRACHVERSION ENGLISCH Language version English
S876A FUNKFREQUENZ 315 MHZ Radio frequency 315 MHz
S992A STEUERUNG KENNZEICHENBEFESTIGUNG Control of number-plate attachment

[E53inLA]

With headlight switch in Auto position:

Start engine
Only Pax side Zenon light is on, driver side is off.
Both amber lights on
Headlight trim decal lights are on all 4 (both Xenon & both Halogen) I'm jnot sure what these are really named, but they are decorative lighting only.
Fog lights turn on & off properly by switch

Pull the stick - Both inside Halogen high beams turn on
Push the stick - Pax side Xenon bulb goes to high beam. Driver side, there appears to be slight movement inside, but light is off.

I tried doing same with headlight switch in the On (far right) position and didn't see any difference with regard the Xenon lights or high beams.

[TerminatorX5]

and you said that there was a moment when both lights, left and right were on?

going from simple to more complicated, I would troubleshoot the xenon light bulb - (some of them you already have completed)

pull the bulb from the "defective" location and put it into the operating location - if problem moved, problem is with the bulb, if problem remained on the drivers side,

i would pull the ballast from "defective" side and try it out in the operating side - if the problem moved, problem is with the ballast, if the problem remained, then

I would try to source BMW software, or get a mechanic who has BMW software, such as GT1 or INPA and read the status of the LCM

since there are NO fuses protecting the light bulbs, you might have one of the MOSFET transistors gone bad, which will call either for a new (used?) LCM or a repair to existing one... the LCM troubleshooting is more involved thus lets hope that the problem is with the light or the ballast...

[E53inLA]

First he installed brand new Flosser D2S bulbs. That didn't fix the problem.

Then we installed a "used but working" Hella ballast I bought from EBay on the drivers side. That didn't fix the problem. Then we swapped the ballasts, so the one originally on the pax side is now on the drivers side.

In order to isolate whether it was a problem within the headlight assembly, or something further upstream, we removed both assemblies and temporarily hooked them up on the wrong side. Then they both worked.

Then we hooked them back up on the correct side, but the retaining cages were removed, and we only had them held in place with one screw. They both worked.

Then we removed the headlight assemblies, reinstalled the retaining cages, and put it all back together with all the screws... and we are back to square one - Driver side low beam doesn't work.

Will try the software suggestion. Thanks & speedy recovery to you.

Is there any point trying to disconnect battery, wait, and reconnect? I see that often suggested in other threads.