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Discussion Starter #1 (Edited)


If you have Eagle Eyes LED tail lights in your car you might have the problem that after some time one or both tail lights stop working but the brake light still works good. (not turning on when the headlights are turned on, but lights up when the brake is pressed).

The problem is in the resistor controller black box that comes attached to the tail lights that sends the activation signal to the tail light.

Some had reported that if you press the black box the tail lights turn on again for a while but it´s not a fix.

Khoalty used to sell replacement resistor boxes for this problem but I want to share a cheap, permanent and easier solution.

You will need:
hacksaw
soldering pencil and soldering wire
a piece of insulated small wire
electrical tape
tie wrap

Unplug the resistor box from the tail light.

Cut the top of resistor box near the top around the edges using a hacksaw as pictured, don´t go all the way cutting side to side to avoid damaging the circuit, just cut enough material on each side to be able to remove or lift the top of the box


Pop off the lid and expose the circuit



solder a small piece of insulated wire between these two points:




Put the lid back on and tape it. You can also use a tie wrap around the box to prevent the tape from unsticking over time.

Put it back in the car and you're done.


The reason why the tail light fails and doesn't turn on is because somehow the metal in the circuit board between these two points turns non conductive enough over time. Since the voltage passing through is so low, the increased conductive resistance of the material prevents the signal for the tail lights to travel from one point to the other. That's why soldering a piece of wire between the two points fixes the problem.


I did this fix more than a year ago for my left tail light, and since then I never had any problems again, but recently the right side started to fail then I just did the same fix on the other side.
 

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About a year ago (maybe ore) my LH EE tail had this problem I installed the fix from Khoalty. When the RH goes I will definitely use your method. Thank you for sharing! :thumbsup:
 

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Did this to my resistor yesterday, and it definitely works, I used to buy the replacement off Khoalty, but this is way cheaper, easy, and it works. Thanks
 

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This is a great fix, the only problem is that after 3 days it started intermittently working for me again. All the lights work apart from the Brake light (when pressing the brake pedal). - I think the problem I am experiencing is different from the fix you highlighted here.

It only happens sometimes when it is warm, I tested this resistor box on the other tail light light and the same happens. I also re-soldered all of the connections there to make sure its not a cold joint or something.

I am starting to think that there wire bridge doesn't have enough resistance or something to that effect, someone mentioned to use graphite rather than a wire, which seems a little out there...

Do you by any chance have any suggestions? I only ask because I've tried going the Khoalty route but they seem to be out of business and I am running out of options :/

Thank you!
 

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Discussion Starter #6 (Edited)
I had a similar problem years ago with a brake light, I remember the problem was a defective soldering point in one of the big squared gray resistors. Sometimes the red tail light error message just appeared on my dashboard and I had to turn off and restart the car to make the error disappear briefly.



You need to remove the back cover of your taillight and you will see 4 or 5 big gray resistors made of a stone like material, they are soldered on a secondary circuit board.

Unscrew and detach the circuit board and examine carefully every soldering point. Those resistors are big and heavy and they are only supported by two tiny wires soldered to the circuit board, if one of those contact points are loose that could be the cause of the random light failure you're experiencing.

You don't even need to remove the taillights from the car, check every resistor at both contact points, or solder them all again just to be sure they're making a good solid contact with the board and re attach the circuit board or consider using another support method for the resistors like zip ties or something if you experience a lot of potholes and vibration in your area.

Another fix you might want to check is if the ground cable in the car wire harness is in good condition (brown wire at one of outer pins in the connector) they're known to burn and melt over time even with OEM taillights, so what I did was put a couple of wiretaps and bridge the connector with an additional cable just to make sure I´m not depending only on the harness plug.

I hope this helps.



=Aidzer0;18558061]This is a great fix, the only problem is that after 3 days it started intermittently working for me again. All the lights work apart from the Brake light (when pressing the brake pedal). - I think the problem I am experiencing is different from the fix you highlighted here.

It only happens sometimes when it is warm, I tested this resistor box on the other tail light light and the same happens. I also re-soldered all of the connections there to make sure its not a cold joint or something.

I am starting to think that there wire bridge doesn't have enough resistance or something to that effect, someone mentioned to use graphite rather than a wire, which seems a little out there...

Do you by any chance have any suggestions? I only ask because I've tried going the Khoalty route but they seem to be out of business and I am running out of options :/

Thank you!
 

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I had a similar problem years ago with a brake light, I remember the problem was a defective soldering point in one of the big squared gray resistors. Sometimes the red tail light error message just appeared on my dashboard and I had to turn off and restart the car to make the error disappear briefly.



You need to remove the back cover of your taillight and you will see 4 or 5 big gray resistors made of a stone like material, they are soldered on a secondary circuit board.

Unscrew and detach the circuit board and examine carefully every soldering point. Those resistors are big and heavy and they are only supported by two tiny wires soldered to the circuit board, if one of those contact points are loose that could be the cause of the random light failure you're experiencing.

You don't even need to remove the taillights from the car, check every resistor at both contact points, or solder them all again just to be sure they're making a good solid contact with the board and re attach the circuit board or consider using another support method for the resistors like zip ties or something if you experience a lot of potholes and vibration in your area.

Another fix you might want to check is if the ground cable in the car wire harness is in good condition (brown wire at one of outer pins in the connector) they're known to burn and melt over time even with OEM taillights, so what I did was put a couple of wiretaps and bridge the connector with an additional cable just to make sure I´m not depending only on the harness plug.

I hope this helps.


Hello Ralf,

Thank you for the reply! I will definitely check those, I removed those before to check the actual LED’s, the reason I believe it’s the resistor black box is because I have changed over the black box from the working light to the failing light and it seemed to fix it but there is no way to determine that’s the issue.

I have hard wired the ground in as the connectors were melted and oxidized. I also added another ground from the chassis to ensure decent ground.

Thanks for the advice, I will update the thread with what I find! (Probably during the weekend since I won’t have time during the week).


Sent from my iPhone using Tapatalk
 

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Hi just did this to one of my eagle eyes, brake lights has began to work normally, but when cutting open the resistor like the dumbass I am I cut the corner of the circuit off. weirdly enough now the indicator won't work but with the soldering and wire tip I got the brake light back on... should I just say fuck it and be a real BMW driver no indicator or is there a way to solve this problem any help would be appreciated thank you
 
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