E46 Fanatics Forum banner

brake light bulb mystery

1 reading
11K views 31 replies 11 participants last post by  Fokust615  
#1 ·
All, before you dismiss this, please hear me out. I am trying to replace my brake light bulbs and it's "clearly" a 1157 bulb right? well, it is not so simple. All the 1157 I have found so far the pegs/pins on the side are straight (180 degrees) but mine needs that at 150 degrees. See the picture.... I have found before that my 330ci (production 09/2000) has a lot of weird stuff. For example, my chrome exhaust tips are welded on so I can't change the tips easily, etc. If you have any idea what this bulb is and how I can get an LED version it would be great... again, all the 1157 replacements I have found the pins are straight across but mine is at an angle. Thanks for the help


Image
 
#4 ·
all the 1157 replacements I have found the pins are straight across but mine is at an angle. Thanks for the help
Show us the pic of the socket with the "150 deg" Bayonet base? All automotive incandescent bulbs are with 180 pins, most are straight but some have vertical offset pins (they are not straight line but offset and 180 deg opposite.
 
#14 ·
. I am not sure why you have to see it as the bulb picture clear showed the 150 degree.
I only asked for the socket pic, which for sure helped to show that it’s a single filament and not a dual type bulb which is a wrong one to use. Dual filament is for both tail light and brake light in one bulb.
 
#7 ·
My question as well. The bulb carrier is stock from 2000, the bulb I can't remember, since I never worked on the car until just about 2-3 years ago. I have owned this car since 2000, it might be the case for some reason the bulb was still stock but it is sus. The bulb/socket I am showing is the type that is typically the 1157, some people call it the brake light bulb some called it the tail light bulb (from various sources e46 bulbs posts, etc). I am still confused about why this combination was used.

That's beyond the point tho... I have two bulbs like that (left and right), in the two sockets, and it still works, I just want to replace them to LEDs. The thing I am very confused about is I can not find this bulb on the internet for some reason. It seems like a bulb with both height offset and 150-degree rotation offset doesn't exist....
 
#12 ·
First of all, we never use American bulbs (1157 etc.) in German cars. Often the American bulb has a lower output (current draw also) and doesn't satisfy the bulb monitor.

Furthermore American dual filament bulbs have large contact surfaces on the bottom when compared to the German bulb. At times creating a cross contacting issue.
 
#13 ·
Do you have suggestions on what to get if we want LED replacements? If you look even on this forum, most of the threads of the bulb provided these American bulb specs. What proper bulbs and LED alternatives do you recommend. Please tell me what (and where) to get instead of what NOT to get since that doesn't really help.
 
#20 · (Edited by Moderator)
Our 325Ci 9/2002 (technically 2003 model year) has an unusual tail light arrangement. Each tail light has 2 single contact bulbs on each side 1 for brake and 1 for reverse. But the running light socket requires a 2 filament bayonet type bulb.

This is unusual as there's 1 contact on the fixture, but 2 contacts on the bulb (laughing).
But that is how its designed. Only 1 filament is used. The "running light" socket is set up to receive the popular 1157 Bayonet dual filament bulb.

BWM does brighten the bulb intensity with brakes are applied, but does so by varying the voltage with the LCM module on that 1 filament. For our coupe the bayonet bulbs are closet to the truck latch on both sides of the car.

I had to think twice after I noticed. But there can be no mistake .. that's what they did

Perhaps they already had the bulb inventoried for other models.

We've had the 325 for 2 years, and a tail light finally gave out. My smart son was assigned the task .. and came back inside all confused. He decided to refresh all the bulbs but saw a single bulb wouldn't fit.

Sometimes I think BMW did things like that to show themselves clever. Using one filament from a double filament bulb ... and then dedicating an output from the LCM to dim one filament ...
I have to get bag to breath into, I'm passing out laughing.

-OurManDan-
 
#24 ·
All, I have looked through the old thread and think the problem of replacing bulbs with LEDs which then trigger warning lights can be fixed by applying the same process shown here: Tailight Fix

I, however, have a different bulb carrier and want to make sure I am connecting to the right spot. I assume the empty hole (circled in read) is where I will be connecting. If someone can confirm this it would be awesome.

thanks!

Image
 
#25 ·
The issue is LEDs use too little current compared to halogens and the lcm thinks it’s broken when it’s not. This has nothing to do with the ground wire.

There are two ways around it, solder a resistor in parallel which draws enough current the lcm thinks it’s on. The resistor is gonna get very hot so you’ll need a high wattage one. Or, more easily, get bmwscanner 1.4 cable and software and deactivate the hot and cold bulb check on the taillights.
 
#26 ·
The issue is LEDs use too little current compared to halogens and the lcm thinks it’s broken when it’s not. This has nothing to do with the ground wire.

There are two ways around it, solder a resistor in parallel which draws enough current the lcm thinks it’s on. The resistor is gonna get very hot so you’ll need a high wattage one. Or, more easily, get bmwscanner 1.4 cable and software and deactivate the hot and cold bulb check on the taillights.
thanks, any idea what resister? The old bulbs are 10 w at 12 v, so the current should be 0.83A, the LEDs are 4W so, the current draw is 0.33A, so I need to add 0.5A draw at 12v, that means a 24-ohm resistor?

I tried bmwscanner before but couldn't get it to work for some reason. I guess I will give it a shot again.
 
#27 ·
It’ll probably be ok with a bit less than 0.5A. There are canbus led resistor kits you can buy specially for this purpose.

But I prefer the software approach. I don’t like messing with factory wiring if i dont need to.

Once BMWscanner is working it’s just a couple clicks, really easy.
 
#28 · (Edited)
I am going to buy a new amazon cable and give this a try (lost my old one a long time ago during a move). I found all these fascinating since I have owned this car new since 2000, but just recently (last year) start to really work on it so it can be revied (it was in a sorry shape cosmetically but mechanically great, 185k miles). Really appreciate the help man.
 
#32 ·
All, before you dismiss this, please hear me out. I am trying to replace my brake light bulbs and it's "clearly" a 1157 bulb right? well, it is not so simple. All the 1157 I have found so far the pegs/pins on the side are straight (180 degrees) but mine needs that at 150 degrees. See the picture.... I have found before that my 330ci (production 09/2000) has a lot of weird stuff. For example, my chrome exhaust tips are welded on so I can't change the tips easily, etc. If you have any idea what this bulb is and how I can get an LED version it would be great... again, all the 1157 replacements I have found the pins are straight across but mine is at an angle. Thanks for the help


View attachment 955937
All, before you dismiss this, please hear me out. I am trying to replace my brake light bulbs and it's "clearly" a 1157 bulb right? well, it is not so simple. All the 1157 I have found so far the pegs/pins on the side are straight (180 degrees) but mine needs that at 150 degrees. See the picture.... I have found before that my 330ci (production 09/2000) has a lot of weird stuff. For example, my chrome exhaust tips are welded on so I can't change the tips easily, etc. If you have any idea what this bulb is and how I can get an LED version it would be great... again, all the 1157 replacements I have found the pins are straight across but mine is at an angle. Thanks for the help


View attachment 955937
I am having the same issue, except I've got 1156 bulbs, not 1157's and the same offset 7225 bulb you show here. I have not been able to find an led replacement that fits either, still trying. I've got a 2002 325ci vert w/sport pkg production date 01/02.