Dim Passenger Headlight - bulb/adaptive/control/etc?

[itranyesterday]

Hi Team,

Brand shpankin new owner of a 2012 135i M-Sport here. Stupidest smile on my face driving home & I'm in love. Of course w/ a 13 y/o car comes 13 y/o problems; one of which being the passenger side headlight is dimmer than the driver side.

QQ to you pros: is this a bulb issue (DRLs right)? & if so, anyone have recommendations on a good replacement (to change both same time).

Or if it's something else then lord help me.

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[itranyesterday]

Bump. Anyone have any thoughts?

I'm thinking of shipping the FRM to get it refurbed.

I also do want those Lux Angel Eyes...if I get them, will this issue persist?

[awns729]

I'm confused because you mentioned DRLs and you're showing a picture of just the angel eyes on and only on one side.

Daytime running lights are done through halogen bulbs and involve only lighting up the round halo rings. Headlights are through a xenon bulb (for certain specs, looks like including yours?).

The halos usually have one ring brighter than the other on each side - just how it is for our older cars.

If your xenon headlights are actually dimmer on one side, I'd start with replacing the bulb itself. They lose brightness over time. I don't think FRM refurb will help you here - all it does is send a signal. There are ballasts (igniters) for the bulbs, and if the bulb itself doesn't help, that might be something to research next. Although I'm not sure how frequently they go bad.

[itranyesterday]

Originally Posted by awns729

I'm confused because you mentioned DRLs and you're showing a picture of just the angel eyes on and only on one side.

Daytime running lights are done through halogen bulbs and involve only lighting up the round halo rings. Headlights are through a xenon bulb (for certain specs, looks like including yours?).

The halos usually have one ring brighter than the other on each side - just how it is for our older cars.

If your xenon headlights are actually dimmer on one side, I'd start with replacing the bulb itself. They lose brightness over time. I don't think FRM refurb will help you here - all it does is send a signal. There are ballasts (igniters) for the bulbs, and if the bulb itself doesn't help, that might be something to research next. Although I'm not sure how frequently they go bad.

Appreciate the response!

I might be confused as well; I think the previous owner coded the angel eyes to be on at all times (which is why I assumed DRLs).

Tried switching ballasts & bulbs but same side stayed dim. Replaced engine ground strap as well as I heard that could've been the issue. Found that there were two straps there for some reason.

But I think the options now would be:
- Bulb is offset & not hitting the angel eye ring properly
- FRM
- Say f it & get new headlights

[awns729]

Originally Posted by itranyesterday

Appreciate the response!

I might be confused as well; I think the previous owner coded the angel eyes to be on at all times (which is why I assumed DRLs).

Tried switching ballasts & bulbs but same side stayed dim. Replaced engine ground strap as well as I heard that could've been the issue. Found that there were two straps there for some reason.

But I think the options now would be:
- Bulb is offset & not hitting the angel eye ring properly
- FRM
- Say f it & get new headlights

I'm not even sure that needs coding. My 2008 has a setting in iDrive for DRL that turns the angel eyes on. I think the voltage provided to the halogen bulbs that are used is low to increase longevity since they're DRL - maybe like 10 or 11 volts - not sure. However, there is a setting if you know how to code the cars, which will increase the voltage to the DRL bulbs so that they become brighter. IIRC I did this a few years ago to make them look brighter like the newer cars with LEDs.

Other things to note:
1) One of the two rings is always brighter on each side because it's closer to the bulb. That's just how BMW designed it.
2) LED bulb upgrades or the coding to increase the voltage will make things look more consistent. Both rings will be brighter and more like modern lights.

If you posted a picture of your car in the original thread, obviously someone has replaced the bulbs if the DRLs are that yellow. I know you said you switched bulbs and ballasts, but are you sure you switched the correct ones that drive the angel eyes? The ballasts have nothing to do with this IIRC, just fyi. If you definitely switched the correct bulbs around from side to side and it's still a problem, then yes it probably has to do with how the bulb is sitting or maybe something is phsyically broken in the light itself. It wouldn't hurt to post a picture of both headlights so we can compare and make sure we understand each other.

[awns729]

Also if you're comparing the brightness of the outer halo rings on both sides, make sure you stand exactly in the center of the car and far away lol. I know it's silly, but the outer rings just get "leftover" light like I said and it really depends on the angle you view it from, so if you position your head exactly in front of one headlight and are comparing the two, one might look a lot brighter than the other.