[Snoopy1501]

Hi all,
I'm wondering if anyone has any ideas on my current problem. I have xenon headlights and the left high beam does not work, but he low beam is working. I've tried searching for all kinds of info, but found bits. As far as I know, there is only a single xenon bulb to power the low and high beams. There is supposedly a shutter that allows the change in light brightness or something to allow the high beam to work. If this is correct, it would seem that the fuse, bulb and ballast are working. Could it be the control module or shutter? I can't seem to find details on the whole assembly and wiring to dig any further. Thanks for any help or guidance.

[pungo]

Welcome to the forum...
There's a shutter solenoid that exposes the lower part of the projector reflector, when engaged for the high beam, you can hear it click if near the light. Pin 5 applies 12v to engage it for the high beams. The solenoid doesn't fail often so I'd check the wiring and connections. The FRM triggers pin 5. Use ista+ to diagnose, there may be some error codes.

[Snoopy1501]

Hi Pungo,
I will give that a check. I don’t have ista+, but will listen for the solenoid and check for voltage. I am not getting any error messages from the car and the high beam indicator shows that it is working.

Thanks

[Snoopy1501]

Good and bad news. The shutter did not click on the left headlamp vs the right, which worked. Pulling the solenoid wire out, I checked for voltage. The left plug did not register any voltage. I did see fluctuating milli-volts, which may say that it was not shorted. I checked the right and it did register 12V. The good news is possibly I do not need to buy a really expensive light assembly. The next step is determining if I have a bad lighting module, which is also not cheap. I was really thinking of hot wiring the right side shutter wire to the left side. I don't know enough to say if this is bad or not. In theory, the shutter should be low current and not put too much load on the driver. This is all assuming that the shutter power is not fused. That I do not know, but I don't believe so. As many would know, it's a pita to access that fuse box behind the glove compartment to check all the lighting fuses.

[pungo]

Looks like you're on the right path. Looks like the left and right wires for the solenoids should be connected together. Also make sure the ground for the solenoid is good.

This diagram should help:

[pungo]

double post deleted

[Snoopy1501]

Looks like I did not get a good voltage measurement, despite a few tries trying to find a good ground. I had jumpered the wire from the other side and still no good. Measured the voltage and no 0V. Eventually, I must have hit a good metal and it was getting the 12v for the shutter wire. My brain was probably not functioning as I did not check the ground wire for the shutter. I will check tomorrow. I have a feeling it will be good, which means I may have a bad shutter.

Another thought that just came to mind as I really start to understand this bi-xenon setup. I happen to recollect that left high beam does not work despite pulling or pushing for the high beam. I see that the right works and hear that shutter. Not sure if this means anything. Could it be the control module of the high beam stalk on the steering wheel?

If it is the shutter, I am assumimg that it cannot be fixed as it is a sealed unit? Or is there some surgery that I could do? Or any ideas where I might find used headlight assembly.

Thanks

[pungo]

Measure the continuity between the 2 pins on the solenoid, should be in the 25-50 ohm range. It's a coil of very thin wire and could be open. If you have continuity, try to manually move the shutter to see if it moves in case something is hanging it up.

If you look at the drawing, there's not a separate fuse for the left and right side, besides, didn't you say you measured 12v at the wire?

Without the headlights even on, you can connect 12v and ground directly to the 2 pins on the solenoid and it should trigger it.

I don't know if you can remove the projector out through the rear on a F25 headlight since I've never tried it, but many other BMW you can, which I've done. If true and the solenoid proves to be bad, you could buy a cracked up headlight from a junkyard or ebay and swap the projector, otherwise a good used headlight is not going to be cheap.

[Snoopy1501]

Thanks pungo for such detailed steps. I will give those steps a shot

[Snoopy1501]

I finally got back to the headlight after the holidays and getting laid off. It's all good. Early retirement and a chance to do what I want.

So I tested the solenoid with an ohm meter. I got 20 ohms, a little lower, but not open. I then applied 12V to the pins. The solenoid worked, but the clicking sound was not as loud as the working side. It sounded like the shutter was not physically moving.

After finding a few videos on F25 bumper removal, I then worked to removed it. The videos showed the top and bottom bolts/screws, the wheel well trim and bolts on the ends of the bumper. They left out a few connect points like 2 bolts on either side inside the kidney grills, which could be reached from the outside. It was tough to get grill out as there were 8 tabs to press to release it. Removing one of the grill made it easier to put the bolts back on later. The small horizontal grill under the kidneys has tabs connecting to another point behind it. I got these off from the side after prying the bumper out a little. I didn't neet to take the whole bumper off, but it gave enough room to pry the bumper out and get the headlight assembly off.

Once I got the assembly off, i tested the solenoid some more. It was moving, but I could not see anything else move. I did find what looks to be a pin floating inside the assembly. I suspect that connected the solenoid to the shutter. I could not access the shutter and could not take the projector out. I just gave up and bought a new assembly. At least I found a place that discounted BMW parts. I just installed it and now it works. I can now pass inspection.

Thanks you pungo for help and guidance. It definitely helped me to fix it myself, instead of paying lots.

[pungo]

Originally Posted by Snoopy1501

Thanks you pungo for help and guidance. It definitely helped me to fix it myself, instead of paying lots.

No worries, glad you got it worked out and learned something about the headlight high beam operation. Now you have some spare parts