High beams not working

[Nate4641]

I don't drive my Z4MR that much anymore, but I have noticed at night my high beams have stopped working for awhile now. I replaced both left and right bulbs with factory bulbs this summer and the low beam is working just fine. When I try to turn on the high beam I get a flash, then it just goes back to low beam on both sides. Maybe it'll stay on for a second, but I can't get them to stay on. Do I need to replace the ignition elements (63126907489) or the control unit (63126907488)?

[maupineda]

Are you sure you are not just pulling as in flash to pass ILO push the stalk to leave them on?

[pungo]

Originally Posted by Nate4641

Do I need to replace the ignition elements (63126907489) or the control unit (63126907488)?

It's not either of those parts since they are for the low beams which are working. There's a solenoid inside each projector that moves a shutter to allow the light to shine upward and since neither side are working, I doubt they both went bad.

Like @maupineda said, are you sure you're pushing the lever forward to turn the high beams on?

[garz747]

My car is coded for headlights always on as it was brought into Canada from the USA. Unless i turn the headlight switch to" on" I will only get the flash to pass.. Make sure your switch is in on position.

[Nate4641]

Originally Posted by pungo

It's not either of those parts since they are for the low beams which are working. There's a solenoid inside each projector that moves a shutter to allow the light to shine upward and since neither side are working, I doubt they both went bad.

Like @maupineda said, are you sure you're pushing the lever forward to turn the high beams on?

Yeah lol. Ive had the car for 10 years, I know how the headlights work. I get it though, gotta cover the dumb simple stuff first. The high beams fail to stay on regardless of which direction I move the stalk, though. All I get is a flash then back to low beams.

The thing is, the high beams will work when the car is first started, but after driving for a little while, maybe 15-20 minutes, the high beams just stop working.

[pungo]

Sorry, had to ask about the high beam switch position, you never said they work correctly for the first 15 minutes of the ride, that data point would have eliminated asking about the push position of the switch.
Anyway, it could either be the headlight switch (LSZ), it's a computer in itself, or the high beam switch. I'd say more likely the LSZ.

If you pull the switch and hold it (flash to pass) do they stay on?
Is the headlight switch in the auto mode during your testing? If not, try using it in the manual "on" position to eliminate the auto mode causing the issue.

If it were mine:
I'd use NCSexpert to rewrite the coding to the LSZ just in case any of the coding got wonky.
If that didn't work, I'd look at the voltage on pin 2 & 36 of the light switch when switching the high beams on and see what it's doing. If you get 12v then the problem is downstream.

Here's the schematic for the Bi-Xenon circuit, it's really pretty simple, all the complicated stuff is inside the LSZ.

[Nate4641]

Originally Posted by pungo

Sorry, had to ask about the high beam switch position, you never said they work correctly for the first 15 minutes of the ride, that data point would have eliminated asking about the push position of the switch.
Anyway, it could either be the headlight switch (LSZ), it's a computer in itself, or the high beam switch. I'd say more likely the LSZ.

If you pull the switch and hold it (flash to pass) do they stay on?
Is the headlight switch in the auto mode during your testing? If not, try using it in the manual "on" position to eliminate the auto mode causing the issue.

If it were mine:
I'd use NCSexpert to rewrite the coding to the LSZ just in case any of the coding got wonky.
If that didn't work, I'd look at the voltage on pin 2 & 36 of the light switch when switching the high beams on and see what it's doing. If you get 12v then the problem is downstream.

Here's the schematic for the Bi-Xenon circuit, it's really pretty simple, all the complicated stuff is inside the LSZ.

Attachment 2759717

I'll have to give that a try this weekend. The high beams don't stay on in both stalk locked forward and stalk pulled and held back. I will have to try the AUTO vs. ON headlight switch to see if that makes a difference, but I don't think it will.

[tomjonesBT33]

Have you tried pulling codes? As previously stated, the LSZ switch might have issues.

[F360C]

Originally Posted by Nate4641

I'll have to give that a try this weekend. The high beams don't stay on in both stalk locked forward and stalk pulled and held back. I will have to try the AUTO vs. ON headlight switch to see if that makes a difference, but I don't think it will.

Funny enough I had the same EXACT same thing happen to me the end of last year. Turn high beams on, they would flash and then turn off. Low beams worked just fine. Sometimes I could cycle the lights and get them to work again, others I had to turn the car off/on and sometimes just couldnt get them to work. What I found strange is that both lights would fail at the same time and would start working again at the same time so i think that rules out an issue with the lights themselves.

Anyways when it happened it was the end of the driving season so I didnt really spend time diagnosing it. Car sat over the winter and funny enough didnt have the issue at all this year.

[Nate4641]

Took the car out the other night and couldn't get the issue to come up again. Tried with the headlight switch on Auto and On, and both pulling and pushing the stalk. I wasn't out for a long drive though, maybe 10-15 minutes.

[pungo]

Originally Posted by Nate4641

Took the car out the other night and couldn't get the issue to come up again. Tried with the headlight switch on Auto and On, and both pulling and pushing the stalk. I wasn't out for a long drive though, maybe 10-15 minutes.

I've been in the electronics field for 40 years and sometimes those types of intermittent faults are explain-able, so we just chalk it up to Voodoo
If I had to guess, I'd say there's a marginal transistor within the LSZ that over time and or with heat fails to send 12v to the Bi-Xenon high beam shutter solenoids. Hopefully it continues to work properly for you.