[brad bedell]

As these cars are going out of warranty, you guys might want to know about this cheap fix. I'll do the other light after I make sure this one is good. When I do, I'll write up a DIY.

History Overview:
Service bulletin:
"SUBJECT
LEDs in Rear Lamp Inoperative
MODEL
E90 (3 Series) from August 31, 2008 to February 2, 2010
SITUATION
The LEDs (Light Emitting Diodes) in the outer left or outer right rear lamp are inoperative. Affected are the
LEDs for the parking lamp/tail lamp or the turn signals. No Check Control message is displayed.
CAUSE
Corrosion of an internal connection within the tail lamp
CORRECTION
Replace both outer rear lamps (left and right), even if only one side is inoperative. Refer to Repair Instruction
REP 63 21 180.
All lamps are to be retained intact by the dealer, awaiting either:
A parts 1. return request to send parts to BMW
An indication to scrap the parts based on information provided in the dealer's scrap report, at which time the parts are to be destroyed to prevent reuse."


That leads me to today:

I picked up some of these 'warrantied lights' recently for the purpose of trouble shooting. It's certainly NOT the connection in my case. However, if it were the connection, a bit of dielectric grease on the contacts will prevent the corrosion. BMW certainly knows this and would have 'cleaned the connection and used some grease' instead of replacing all the lights.

I suspected they had a bad solder joint. So I disassembled the lights and re-flowed the joints at the connectors between boards. I noticed when bench testing with a 9v battery that I could get them to all light up and flicker a bit if I put pressure on the solder joints.

The light came apart reasonably easy with a small screw driver. I pried them apart slowly by twisting the screw driver. They are glued on with a plastic cement or maybe even something like superglue. It's a very light bead, so breaking it apart was pretty easy. Sealing them back up will be a bit more of a chore, but not impossible. I'll get the big boy camera out to reassemble them after I repair the board.

Anyhow, this is the initial bench test:



I touched up the solder joints at all these connections shown by the pen. (at all the white wire connections)






I need to hook it up to a 12v power source to verify. I'm just using a 9v battery.


After testing a few times. I decided to stress test my 'fix' and toss it around on my desk a little and retest after each 'toss' to look for bad connections. I found I had to retouch a few of LED's. They were easy to identify by pressing down lightly with my finger on the LED itself.


Looking at the board, most of the connections are not shiny like a good solder joint. They are dull which leads me to believe the manufacturer of these boards didn't program their robot quite right. It probably needed a bit more solder and a couple more milliseconds of heat.

[JBizzle]

very nice work, Brad!

[brad bedell]

I glued it back together. I'm not real comfortable about it being leak sealed. I'll be flowing some clear windshield sealant in there after I verify it's working 100%. I feels these things can come apart once at the most. The 2nd time might be doable if you used the correct type of glue/sealant.

Adding some more random peeksures:

Assembly without the LED bits:


LED bits, with chrome:


Another of the housing:

Just the lens:

[brad bedell]

Caveat for those of you who might want to try this:

You know the TV CSI trick where they get fingerprints from super-glue vapor? Lets just say, it's not fiction.

I've got super-glue vapor prints inside the rear light now.... I guess I'll see if it comes apart a 2nd time.

[brad bedell]

it's a parts light now.. bummer. Cracked the lens when I took it apart the 2nd time. those marks were NOT there before the superglue vapors. Pretty cool that it actually works.

[mapleridge]

Hi Brad,

thanks for posting this. I will make sure to wear gloves when dealing with my housings. Also, can you explain what you mean by reflowing and what the process is for adding solder to the points you mentioned? I need to repair my light.

[Dark_Knight_335]

Wow man, that is some badass work there. Wish I had your talent- I'm petrified to touch anything like that!

[GoRomeo]

Indeed, thanks for sharing such great info. Though I dont have these issues....

[Game]

If anyone is looking for a LCI tail light project -

http://www.e90post.com/forums/showthread.php?t=785168

[taibanl]

Sub'd

[brad bedell]

Originally Posted by mapleridge

Hi Brad,

thanks for posting this. I will make sure to wear gloves when dealing with my housings. Also, can you explain what you mean by reflowing and what the process is for adding solder to the points you mentioned? I need to repair my light.

Tin the tip of your soldering iron and touch the solder joint for a second. Too long and you'll overheat the surface mounts. On the wire contacts, I added a bit of solder. You'll want to use a high quality iron with a very fine tip.

When these were assembled they were likely baked in an oven or assembled by robot. They can be hand-repaired, but it's delicate work. If you've never done work like this before, expect to ruin the first light. However, if you're trying this, you've given up on the chance of a warranty anyhow.

[ERIC212NYC]

Could you post a couple of more pictures of where to solder the points? I had mine replaced twice, but now I am out of warranty and it the problem cropped up again.

I saw a picture of someone cutting the plastic on the inside to remove the board. Not sure if that is a good idea or not.

This is a very annoying problem.

[mapleridge]

Originally Posted by ERIC212NYC

Could you post a couple of more pictures of where to solder the points? I had mine replaced twice, but now I am out of warranty and it the problem cropped up again.

I saw a picture of someone cutting the plastic on the inside to remove the board. Not sure if that is a good idea or not.

This is a very annoying problem.

Removing the plastic might be easier to seal up. The mexican forum where that is listed the guy says he plastic welded it shut again. Sounds pretty good to me. I have this problem and I don't know which method I am going to try yet.

[elcheapoloco]

Dull solder joint points to a few possibilities, most likely:

1. Not enough flux
2. Flux not sufficiently cleaned after reflow, causing oxidation.

Both will cause loose/weak solder joints. All you have to do is dab rosin flux on existing solder joint and apply heat with solder iron. You will see the solder joints turn shiny, immediately remove heat. Be sure to remove remaining flux with alcohol. Rosin flux won't cause oxidation as much as water-based flux, but it's acidic nonetheless.

[Dominus]

I have a passenger set if anyone wants a cheap project one:http://www.e90post.com/forums/showthread.php?t=802015

[brad bedell]

Originally Posted by elcheapoloco

Dull solder joint points to a few possibilities, most likely:

1. Not enough flux
2. Flux not sufficiently cleaned after reflow, causing oxidation.

Both will cause loose/weak solder joints. All you have to do is dab rosin flux on existing solder joint and apply heat with solder iron. You will see the solder joints turn shiny, immediately remove heat. Be sure to remove remaining flux with alcohol. Rosin flux won't cause oxidation as much as water-based flux, but it's acidic nonetheless.

Thanks for clarifying. They were dull from the factory. Not sufficiently cleaning the flux could cause the delayed failure. It's hard to say.BMW is collecting them and destroying them as often as they can on warranty.

For those who asked about getting them apart. I just used a small screwdriver and slowly worked around the lens mechanically forcing it apart. A hot knife or something else might be a better option. I don't have much experience at taking these apart. I'd lean toward a clear bead of tub and tile silicone for reassembly. It'd be water tight and could be pealed apart if necessary.

Like I said before, I cracked it the second time I attempted to take it apart. If you do take them apart, be prepared to crack them as it's very easy to do.