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      10-11-2022, 06:00 AM   #155
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Quote:
Originally Posted by Jinjer View Post
Heya!
Same issue on my M2's right side. Since dirty and water is going in, I don't think that bending the pins is the answer but finding a solution so nothing gets in anymore. In search for a solution. If someone has any idea, please let me know. Thanks.
This is how it looks after 2 weeks of cleaning it.
It's not a great design, if you take the light unit off you'll see the entire thing and the connectors and wiring sits OUTSIDE the vehicle shell in full exposure to the elements and the rear window / boot/trunk gutter drainage which gets full of crud and muck.

All previous cars I've had the light units sat over a sealed aperture in the body work so the wiring and connectors sat INSIDE the vehicle shell in the warm and dry.

Mines been fine all summer, but I now come November / cold / damp it will start acting up again....
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      10-11-2022, 10:29 PM   #156
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Quote:
Originally Posted by Jinjer View Post
Heya!
Same issue on my M2's right side. Since dirty and water is going in, I don't think that bending the pins is the answer but finding a solution so nothing gets in anymore. In search for a solution. If someone has any idea, please let me know. Thanks.
This is how it looks after 2 weeks of cleaning it.
Well, I have no idea how easy it is to disassemble the light, but I would conformal coat the entire PCB if it's easy enough. Might not do anything, but it's not hard if you have experience. There's just no evidence that the failure is related to water or anything environmental at the moment.
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      10-12-2022, 12:53 AM   #157
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Quote:
Originally Posted by chris719 View Post
Well, I have no idea how easy it is to disassemble the light, but I would conformal coat the entire PCB if it's easy enough. Might not do anything, but it's not hard if you have experience. There's just no evidence that the failure is related to water or anything environmental at the moment.
I think there's plenty of evidence that for many the fault is related to the connector in particular. Deteriorating over time to give a higher resistance connection that triggers the lamp fail warnings.

Probably exacerbated by environmental factors.

Initially mine had got to failing daily, clean the connector and not a single fault for a year.

Then it started again in cold & wet conditions.

Now i just give the light a whack and it works fine 🙂

Other faults on other cars may vary of course..
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      10-16-2022, 10:39 AM   #158
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Good info in the thread. I haven't had this issue yet. Mine is a January 2020 build with close to 25k miles and (sadly) park outdoors in SEATTLE where it rains frequently.

It seems the issue is potentially a mixture of incorrect factory coding and hardware aging out of spec?

I haven't checked BimmerCode on mine but I wonder if at least the coding was fixed in later build dates? If incorrect coding can exasperate the issue then I'm surprised I haven't had this come up given the car's age and exposure to rain.

Any reports of 2021s getting the issue? Anyone with the issue on a 2020 have a build date later than January?
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      10-23-2022, 04:31 PM   #159
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Hello everyone.
I got an F22 220d from 2014 and upgraded my taillights to LCI because of the burnt mass cable problems that the PRE LCI got. I Pinned and connected the right side first and let the left side pre-LCI.
But on the right side the indicator doen't work. I've never seen it blinking once and the indicator in the cluster is blinking supafast. Even playing the bongo song with my local band didnt work. I tried to exchange the rear fog light with the indicator pin to check if the LED for the indicator is broken but it keeps lightning permanently when they are swapped. When i use the indicator the rear fog light stays OFF.
Maybe someone has some help for me im searching for days now and im an newbie. I tried to open the light but i want to keep it for the last opinion.

Edit: The guy i bought them from told me the Right one had an error. Any advices to fix the Right indicator? Im not a fan of throwing things into garbage i would like to fix them on my own
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      10-23-2022, 06:05 PM   #160
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Quote:
Originally Posted by Poochie View Post
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Originally Posted by pablom2c View Post
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Originally Posted by Poochie View Post
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Originally Posted by pablom2c View Post
Well it looks like I jinxed myself haha… after about a year of the coding fix working, yesterday I noticed my rear left indicator was not working (did not get dash warning of course due to coding). It has been raining a lot lately over here, but there doesn't seem to be water inside the tail light. Maybe the humidity has something to do with it? The indicator looks like it was working but very very dim, in day light you can't see it but at night it is very faint you can see it up close. I saw a post that said to tap the tail light and I did a few times and then the indicator started working again normally. Is this a different fault to the coding fix? Should I check the wires or get a replacement headlight? Mine is a 2020 M2C. Are all the headlights that BMW replaces for free the same part number? There is no new updated version? Maybe there is more than one type of fault with these tail lights?
How and what did you change in the with coding?

That sounds like a programming issue, go back to "Expert Mode" under REM and change these four parameters to "active."

The reason your light flickers when the turn signal is illuminated is because the frequency of PWM (Pulse Width Modulation) is too slow. This change will eliminate that and give you working LED signals.
I used Carly to disable the bulb checks but I'm fed up with that app. I ordered a new adapter to use with Bimmercode and will try the expert mode configs maybe like you mention there is some coding missing there. But why would the indicator start working again after hitting the tail light?
Honestly, I believe that was just a coincidence; the circuit board of which turn signal LEDs are embedded on are locked into place and is insulated from shock within the taillights, with layers of hard plastic, that knocking the outer shell really has no effect on the LEDs itself or it's power connection.

I wish I had saved all the photos I took because I had (literally) crack open a taillight just to examine its components and as you see from the photo below, the circuit board slides into a locking hardness and outer wire harness clips unto the taillight, which has no play or any gaps for water intrusion. By design, you can take a baseball bat to the taillights, crack the outer plastic open and the inner taillight LEDs would experience little or no physical shock and still function as normal.

I'm pretty sure you have a coding issue because I recognize the error you have. I experienced the same dimming/flickering turn signal prior to coding my pre-LCI incandescent settings to LEDs. The reason this happens is because the rear computer for the turn signals is sending the wrong modulation signal to the turn signals because it's assuming incandescent (not LEDs) are installed.

Try my coding suggestion, you really have nothing to lose. As long as your warranty is still active, BMW will still replace the taillights and whatever other components they feel like, an unlimited number of times until the warranty expires, if you are not satisfied with the results but I'm certain the proper coding will correct this issue.

I never tried Carly so I can't speak on that but I know BimmerCode is extremely intuitive and so worth the $30. Their customer service is also helpful and respond almost immediately, so you certainly get your money's worth IMHO.


.
Quote:
Originally Posted by Poochie View Post
Quote:
Originally Posted by pablom2c View Post
Quote:
Originally Posted by Poochie View Post
Quote:
Originally Posted by pablom2c View Post
Well it looks like I jinxed myself haha… after about a year of the coding fix working, yesterday I noticed my rear left indicator was not working (did not get dash warning of course due to coding). It has been raining a lot lately over here, but there doesn't seem to be water inside the tail light. Maybe the humidity has something to do with it? The indicator looks like it was working but very very dim, in day light you can't see it but at night it is very faint you can see it up close. I saw a post that said to tap the tail light and I did a few times and then the indicator started working again normally. Is this a different fault to the coding fix? Should I check the wires or get a replacement headlight? Mine is a 2020 M2C. Are all the headlights that BMW replaces for free the same part number? There is no new updated version? Maybe there is more than one type of fault with these tail lights?
How and what did you change in the with coding?

That sounds like a programming issue, go back to "Expert Mode" under REM and change these four parameters to "active."

The reason your light flickers when the turn signal is illuminated is because the frequency of PWM (Pulse Width Modulation) is too slow. This change will eliminate that and give you working LED signals.
I used Carly to disable the bulb checks but I'm fed up with that app. I ordered a new adapter to use with Bimmercode and will try the expert mode configs maybe like you mention there is some coding missing there. But why would the indicator start working again after hitting the tail light?
Honestly, I believe that was just a coincidence; the circuit board of which turn signal LEDs are embedded on are locked into place and is insulated from shock within the taillights, with layers of hard plastic, that knocking the outer shell really has no effect on the LEDs itself or it's power connection.

I wish I had saved all the photos I took because I had (literally) crack open a taillight just to examine its components and as you see from the photo below, the circuit board slides into a locking hardness and outer wire harness clips unto the taillight, which has no play or any gaps for water intrusion. By design, you can take a baseball bat to the taillights, crack the outer plastic open and the inner taillight LEDs would experience little or no physical shock and still function as normal.

I'm pretty sure you have a coding issue because I recognize the error you have. I experienced the same dimming/flickering turn signal prior to coding my pre-LCI incandescent settings to LEDs. The reason this happens is because the rear computer for the turn signals is sending the wrong modulation signal to the turn signals because it's assuming incandescent (not LEDs) are installed.

Try my coding suggestion, you really have nothing to lose. As long as your warranty is still active, BMW will still replace the taillights and whatever other components they feel like, an unlimited number of times until the warranty expires, if you are not satisfied with the results but I'm certain the proper coding will correct this issue.

I never tried Carly so I can't speak on that but I know BimmerCode is extremely intuitive and so worth the $30. Their customer service is also helpful and respond almost immediately, so you certainly get your money's worth IMHO.


.
Is there a way to fix them by opening the taillight ?
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      11-17-2022, 05:35 AM   #161
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6 months in and the REM module replacement is still holding steady. The problem has not returned to date. I park outside in the weather and it rains a lot, so it's a torture test for sure. We'll see if it continues to hold.
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      01-17-2023, 06:39 PM   #162
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Mine is acting up again.

I disconnected it and cleaned it, and the left indicator doesn’t light up completely.

Only fix is giving it a tap and it gets fixed but with the horrible roads around here it will get shaken up on every drive.

So there’s not really a fix but keep replacing the tail lights? Not even the coding helps.

Only hope is the REM module replacement? Any update on that?
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      01-17-2023, 07:12 PM   #163
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Quote:
Originally Posted by pablom2c View Post
Mine is acting up again.

I disconnected it and cleaned it, and the left indicator doesn’t light up completely.

Only fix is giving it a tap and it gets fixed but with the horrible roads around here it will get shaken up on every drive.

So there’s not really a fix but keep replacing the tail lights? Not even the coding helps.

Only hope is the REM module replacement? Any update on that?
I don't quite understand how it's the REM if replacing the light always makes it go away for at least several months. It's not impossible the issue is in the REM but it's less likely than the light.
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      04-25-2023, 11:57 AM   #164
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Just to provide an update on both of my faulty rear turn signal indicators, I have now received and installed both new rear tail lights and now both indicators work correctly, let's see how long they last... I will keep the LED coding.
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      04-25-2023, 01:58 PM   #165
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I replaced my left tail light on my own 2 weeks ago for this failure. It would do it most often in the cold. 2019 M2C, just out of warranty, I simply had not taken it to the dealer in time for it.

I simply ordered a new tail light and installed it myself. So far so good.
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      05-27-2023, 05:14 PM   #166
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Whelp finally happened to me, right turn signal malfunction. 2020 with 9600 miles garage kept. It is totally random, sometimes it’s fine, sometimes it pops up, most of the time it doesn’t do the fast blink.

I was thinking this might be an excellent use for fcpeuros lifetime warranty.
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      05-27-2023, 10:57 PM   #167
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I removed the taillights and cleaned the connectors (not that they were particularly dirty), bent the pins down ever so slightly, and put everything back together just about a year ago. Issue hasn’t recurred since. 2018 M2 LCI
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      05-27-2023, 11:26 PM   #168
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Quote:
Originally Posted by enjanir View Post
I was thinking this might be an excellent use for fcpeuros lifetime warranty.
I’ve been thinking the same thing! Last I checked, FCP Euro doesn’t carry the LCI/M2C taillights — they just have the OG taillight assemblies in stock. It’ll be great when (if?) they start carrying them!
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      05-28-2023, 10:51 AM   #169
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Quote:
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I’ve been thinking the same thing! Last I checked, FCP Euro doesn’t carry the LCI/M2C taillights — they just have the OG taillight assemblies in stock. It’ll be great when (if?) they start carrying them!
I actually emailed their support last night to inquire about the exact same thing.

2014-2017: unique part numbers
2018-2019: unique part numbers
2018-2021: unique part numbers

After some searching on the eurospec amber turn signals the parts numbers from
Schmiedmann can be ordered on getbmwparts as well. All are approximately $220 usd.
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      05-31-2023, 10:08 AM   #170
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Update from FCPEuro... No current plans to add M2C led taillights to the site (63-21-9-491-593 and 63-21-9-491-594) ugh, I guess more people need to start asking for those part numbers.
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      05-31-2023, 12:24 PM   #171
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I removed the taillights and cleaned the connectors (not that they were particularly dirty), bent the pins down ever so slightly, and put everything back together just about a year ago. Issue hasn’t recurred since. 2018 M2 LCI
Folks laughed when i bent the pins on mine to increase contact pressure.

It's been fine so far this year, which is much longer than it ever went previously.

🤞
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      06-04-2023, 01:07 PM   #172
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My car started having the turn signal hyper flash intermittently after about 3 years. Since I already knew how to recode for LED lights from my M235 days, I did the same coding on my M2C. Guess what, the turn signals gave never hyperflashed again. I think BMW didn't get their programming right after the switch to LEDs. You just have to program out the bulb check which BMW probably won't do for regulatory reasons.
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      06-06-2023, 09:46 PM   #173
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I think BMW didn't get their programming right after the switch to LEDs. You just have to program out the bulb check which BMW probably won't do for regulatory reasons.
We've been through this on other threads. I doubt it, it would be trivial for them to increase the tolerance to the voltage drop in the software. Fact is, the tails pass the check until they age, and there is no good reason for that to happen. They also wouldn't be replacing tails under an extended warranty for 10 years if they could fix it with a boundary value check adjustment in software.

That said, I expect this will work for quite a while.
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      06-07-2023, 04:49 AM   #174
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You just have to program out the bulb check which BMW probably won't do for regulatory reasons.
I did this, but then you get no warning when the turn signal fails again, so you just have no turn signal.

I had to turn warm check back on so every few weeks when it fails at least I know about it and can get out and give it a whack, good to go for a few more weeks...
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      06-08-2023, 11:10 AM   #175
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I did this, but then you get no warning when the turn signal fails again, so you just have no turn signal.

I had to turn warm check back on so every few weeks when it fails at least I know about it and can get out and give it a whack, good to go for a few more weeks...
So did you actually witness the bulb not working? In my case the bulb always worked, it would just hyperflash sometimes.
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      06-11-2023, 12:55 AM   #176
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Yes the turn leds go very dim and only a small number of them come.

Give it a whack and they all come back
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