LED replacements and dash warning

[kbcons]

Doing some early exploring regarding LED replacements for front corners, sidemarkers, tail lights, rear turn signals, backup lights.

Will replacement of these will cause a dash warning? There's a fair amount of anecdotal evidence that tails will, but what about the others?

Thanks!

Ken...

[BMWCurves]

Talk to BP, he's doing a lot of LED lighting. I believe you can find decent LED lights on eBay for the tails by searching "LED canbus XXXX" where the XXXX is the bulb number.

[az3579]

You need CANBUS bulbs. These are bulbs that have built-in resistors, so they will not hyperflash, nor will they cause bulb out errors.
For best results, you should get ones that utilize CREE chips - they are the brightest of the ones I've tried. I've gone through a few different kinds...

I have CREE LEDs in my front and rear turn signals, fog lights, brake lights, and reverse lights. I left the running lights alone with halogen because the CREE bulbs I put in were way too bright for the "half brightness" they're supposed to be.

BTW, an unfortunate side effect of these LED bulbs is that they seem to cause some kind of interference with my radio reception. Since I rarely use the radio, I don't care all that much (it doesn't affect any other part of the audio system, such as listening via Bluetooth). The static shows up when the turn signals are activated, and has that noise every time the bulbs turn on. In my case, since my brake lights are LED as well, the radio is a bit more staticky when the brakes are applied as well. Granted, my rear glass has the infamous short in it, so I need a new rear glass anyway since the radio reception sucks even without any bulbs being on. I'm sure the static wouldn't be an issue if I had a properly functioning antenna (located in the rear glass).

Also note, you will need coding. With the LED bulbs installed, your lights will very lightly flicker when the car is turned on while it tests the bulbs. This testing can be disabled - it does it when you turn the car on and it does it seemingly randomly while the car is in operation. I've disabled both the cold and warm checks on my car so there is no flickering.

[kbcons]

You need CANBUS bulbs. These are bulbs that have built-in resistors, so they will not hyperflash, nor will they cause bulb out errors.
For best results, you should get ones that utilize CREE chips - they are the brightest of the ones I've tried. I've gone through a few different kinds...

Excellent information! Thanks!

Ken...

[anandoc]

I've disabled both the cold and warm checks on my car so there is no flickering.

Does that mean you will never receive a bulb out warning - even if the LED bulb is actually burned out?

[BMWCurves]

@BP

What bulbs did you end up using for your front turn signals? The set I ordered were too long and didn't fit well/looked weird in the housing.

[anandoc]

@BP

What bulbs did you end up using for your front turn signals? The set I ordered were too long and didn't fit well/looked weird in the housing.

The sedan front corner bulbs (1156/7506) are different from coupe bulbs. BP has a sedan...

[BMWCurves]

The sedan front corner bulbs (1156/7506) are different from coupe bulbs. BP has a sedan...

I know, I'm just trying to see if he found bulbs that were short like the factory bulbs, or if the difference between the bulbs was enough for the added length to not be an issue.

[kbcons]

@BP

What bulbs did you end up using for your front turn signals? The set I ordered were too long and didn't fit well/looked weird in the housing.

I assume you're talking about the LEDs looking weird?

Ken...

[BMWCurves]

I assume you're talking about the LEDs looking weird?

Ken...

The LEDs in terms of lighting looked great. What I didn't like is how they were positioned in the housing because they were longer than the factory bulbs. They basically were pushed against the headlamp housing, like so (LED in passenger signal, factory incandescent bulb in driver's side):


https://www.youtube.com/watch?v=JFAnVvHaGlM

[az3579]

Does that mean you will never receive a bulb out warning - even if the LED bulb is actually burned out?

This is kind of a weird one. Let me break down my findings:

The cold checks from what I can see are the checks it does when you first turn the ignition on. It will send a pulse to the bulbs for a few seconds, at which point it determines if a bulb is dead or on its way out. The LEDs will flicker for a few seconds as they receive the pulses from the LCM during the test. The reason the incandescent bulbs do not flicker is because they require significantly more time to illuminate. The pulses are so short that the incandescent bulbs don't have enough time to illuminate with those short pulses.

Coding out the cold check will eliminate this flickering. The downside is that you will not get an immediate notification that a bulb is out. You'll only get that notification once you go to try to use the bulb. So, say your brake light bulb is out but the cold check is disabled. Your car will not tell you a bulb is out until you press the brake pedal. If cold checks were on, it would tell you right off the bat after turning the ignition on due to the test pulses checking for it.

Warm checks I'm not 100% sure about. My theory is that the warm checks are pulses sent at set intervals while driving. A few people say it's around 5 minute intervals that the LCM sends the warm pulse checks. Based on research I've done and experiences I've had with my car with the warm checks enabled, that information is backed up by what I'm seeing. I've had warm checks enabled but cold checks disabled and I've had people following me tell me that my lights flicker every few minutes, so that makes sense.

I've recently disabled all warm checks with my car in order to completely eliminate flickering. The downside to this is that it seems that it doesn't notify you of failed bulbs at all this way. I tested this while waiting for laundry at the laundromat after seeing your question on the forum. I disabled warm and cold checks, then I took out my turn signal and brake light bulbs.

With the turn signal bulb removed, the turn signal stays constant and does not hyperflash. It also does NOT tell you that a bulb is out, which is a bummer because you wouldn't have a clue based on its normal flash rate. The brake light, however, did tell me about the bulb out as soon as I went to press the brake. I'm not sure why the turn signal failed to misbehave when it should have but the brake light notification acted as expected.

I'd like to re-enable the warm checks and watch the car for about 15 minutes to see if the flickering does indeed happen. If so, that will prove my theory. Ultimately, there was a time when cars didn't have checks for burnt out bulbs, so personally I'd rather just do a visual inspection of my car from time to time and have super bright, good-looking LEDs that don't flicker.


@BP

What bulbs did you end up using for your front turn signals? The set I ordered were too long and didn't fit well/looked weird in the housing.


The sedan front corner bulbs (1156/7506) are different from coupe bulbs. BP has a sedan...

Yes, I do have a sedan and they are different from the 2-missing-door variants. I bought bulbs from eBay, meaning there is no "brand/model" I can give you. The best I can offer you is "25W CREE CANBUS 1156 Amber" or "Red". I have the amber for turns and the red for the brake light portions. The bulbs between the amber and red look exactly the same physically, and have (Qty) 5, 5W CREE XP-E chips (for a total of 25W), which are super bright even in direct sunlight. The red is brighter than the amber due to the wavelength of the light (or so I've been told), but the amber is plenty bright.

I did recently order (3) pairs of 25W Red bulbs for my running lights (bottom row in the tail lights, and trunk light), but I found that they are WAY too bright when in parking light mode and are blinding at night. I don't know why they don't run at half brightness like they are supposed to, but I'm sure there's a technical reason that I don't understand, and frankly don't want to put the effort in researching it. As a result, I reverted the running lights to incandescent bulbs, which is probably a good thing anyway since they are way cheaper to replace and they are on ALL the time (I have them as DRLs).


I know, I'm just trying to see if he found bulbs that were short like the factory bulbs, or if the difference between the bulbs was enough for the added length to not be an issue.

I'll take a pic of the LED bulb next to the factory 1156 incandescent bulb to give you an idea. I'm not sure what socket your front bulbs are though, so the factory length of yours may be different than mine.

[anandoc]

Ultimately, there was a time when cars didn't have checks for burnt out bulbs, so personally I'd rather just do a visual inspection of my car from time to time and have super bright, good-looking LEDs that don't flicker.


BP, thanks for the detailed post and for doing some testing on the fly. One would imagine that if the warm checks were disabled (eliminating the flickering every 5 mins), the cold checks alone would tell you at ignition whether any of the bulbs were out - but I guess the BMW engineers' logic beats ours.

I agree - I can do a visual inspection every so often and rather have bright LED lights. I was able to locate some US based eBay sellers with the 25W CREE bulbs but the shipping and customs were cost prohibitive. Maybe I would have to use my neighborhood parts smuggler's services next time :)



Yes, I do have a sedan and they are different from the 2-missing-door variants.


LOL!

[BMWCurves]

I'll take a pic of the LED bulb next to the factory 1156 incandescent bulb to give you an idea. I'm not sure what socket your front bulbs are though, so the factory length of yours may be different than mine.

I would appreciate it!

[kbcons]

The LEDs in terms of lighting looked great. What I didn't like is how they were positioned in the housing because they were longer than the factory bulbs. They basically were pushed against the headlamp housing, like so (LED in passenger signal, factory incandescent bulb in driver's side):

Gotcha, thanks.

Ken...

[kbcons]

I did recently order (3) pairs of 25W Red bulbs for my running lights (bottom row in the tail lights, and trunk light), but I found that they are WAY too bright when in parking light mode and are blinding at night. I don't know why they don't run at half brightness like they are supposed to, but I'm sure there's a technical reason that I don't understand, and frankly don't want to put the effort in researching it. As a result, I reverted the running lights to incandescent bulbs, which is probably a good thing anyway since they are way cheaper to replace and they are on ALL the time (I have them as DRLs).

This would be something controlled by a driver circuit, which I don't think these LED assemblies have. After all, they are fed by the 12V DC of the car and not household AC current.

Consider this to be the difference between a household dimable LED "bulb" and a non-dimable The non-dimable bulb will only run at full brightness, regardless of the voltage or waveform sent to it.

Ken...

[az3579]

Consider this to be the difference between a household dimable LED "bulb" and a non-dimable The non-dimable bulb will only run at full brightness, regardless of the voltage or waveform sent to it.


Well, the amber turn signal bulbs in the front dim just fine - I have the front turn signals set to DRLs, so they are at half brightness. I think what I'll do is put the amber bulbs into the running light slots and see if they run at half brightness back there as well. If they do, then it's probably the particular red bulbs that I purchased that aren't appropriate. I'll do that when I take out the bulbs for size comparison pics.

[az3579]

Size comparison between stock incandescent 1156 bulb on the left and my LED 1156 bulb on the right. They are almost the same length.

http://uploads.tapatalk-cdn.com/20160721/bca4c58570a350620f7844a3f9735885.jpg



P.S. - Don't buy these - they have garbage light output.

http://uploads.tapatalk-cdn.com/20160721/191544506a5a63362276fae93be9e190.jpg

Sent from my LG V10 on Tapatalk

[BMWCurves]

Appreciate it. I guess I'll have to see if I can find one that is shorter.

[tinuva]

Hi all,

I recently also started adding LED bulbs to my car, mostly bought from JDMaster. Special thank you to az3579's posts explaining the checks, I disabled all warm checks and left the cold checks.

Very happy with the results but have an interesting issue. My side indicators on the fenders, works great but are very dimly lit as soon as the LCM wakes up, and will stay on for about 5 minutes after the car was locked before turning off.

It looks like this:
35959

I suspect the LCM is sending a very low voltage to the side indicators as soon as it wakes up, but I have no idea. The LCM is running 4.5 SW, I retrofitted it to the car.
Would changing PWM values for these help? If so what values should I try.

Thank you in advance!

Here is a short clip testing the bulbs on the rear.

https://www.youtube.com/watch?v=JnPD9tnNWB8

[az3579]

Regarding the sidemarkers,
Yeah I just deal with it. It's not a big deal in my experience.
I haven't found anything I can do about it, though to be fair I haven't looked much either. It doesn't bother me.