Signal Light (Rear) Indicator Clarification

[Schnitzer318is]

I searched here and e30tech with a few combinations of keywords and could only turn up a hyperblnk type of bulb out warning. I'm doing a complete LED rear tail conversion and need some clarification on how our car's lighting works. I did the rear signal with 96 amber LEDs (looks great btw). Everything works properly as it should without a regular bulb in the turn signal spot on the rear bulb carrier. No hyperblnk or anything. As soon as I turn on parking lights or headlights my right turn signal indicator in the cluster illuminates solid and stays lit... and none of the right side signal lights will work properly. If I turn parking lights/headlights off everything works normally again. Now if I put an incandescent in the bulb socket on the carrier everything works fine with the headlights on. Is this a resistance issue? Should I be looking for some sort of electronic flasher to replace the stocker? (EDIT: As a test I removed the flasher unit altogether and as soon as I turn on the headlight/parking lights the right side turn indicator comes on constant, so I'm not sure a relay will fix this issue.) Or is this related to my LED front turn/parking and LED sidemarker conversion? Perhaps if you have no bulbs on a side (front or back) the indicator will not hyperblink but stay on constant to indicate both bulbs have failed? I'm sure this is just the first hurdle with the LED conversion... but hopefully someone here can help out. TIA

BTW I have some questions about the rear check relay as well for when I get to converting the brake lights and parking lights in the tails. But that's another thread.

[DaveSmed]

I searched here and e30tech with a few combinations of keywords and could only turn up a hyperblnk type of bulb out warning. I'm doing a complete LED rear tail conversion and need some clarification on how our car's lighting works. I did the rear signal with 96 amber LEDs (looks great btw). Everything works properly as it should without a regular bulb in the turn signal spot on the rear bulb carrier. No hyperblnk or anything. As soon as I turn on parking lights or headlights my right turn signal indicator in the cluster illuminates solid and stays lit... and none of the right side signal lights will work properly. If I turn parking lights/headlights off everything works normally again. Now if I put an incandescent in the bulb socket on the carrier everything works fine with the headlights on. Is this a resistance issue? Should I be looking for some sort of electronic flasher to replace the stocker? (EDIT: As a test I removed the flasher unit altogether and as soon as I turn on the headlight/parking lights the right side turn indicator comes on constant, so I'm not sure a relay will fix this issue.) Or is this related to my LED front turn/parking and LED sidemarker conversion? Perhaps if you have no bulbs on a side (front or back) the indicator will not hyperblink but stay on constant to indicate both bulbs have failed? I'm sure this is just the first hurdle with the LED conversion... but hopefully someone here can help out. TIA

BTW I have some questions about the rear check relay as well for when I get to converting the brake lights and parking lights in the tails. But that's another thread.

The best place to start is most likely up front. How did you wire all of this to not blink fast? I would suspect a resistor.....

[Schnitzer318is]

The best place to start is most likely up front. How did you wire all of this to not blink fast? I would suspect a resistor.....

Sweet, I was hoping you would chime in here or e30tech due to your knowledge of the check relay. To answer your question, the front is run with relays... one for each side. The parking light and the turn signal wires are run across the coil so that the lights act as both parking lights and turns without hyperblinking. There isn't any incandescent bulb fitted into the front, sidemarker, or rear sockets. Is there a way to short the check relay or bypass it entirely so that it doesn't interfere with the lighting circuit? I replaced the flasher unit (under column) with an LED friendly unit and get the same result as before. I bought a 6ohm 50w resistor for each side to "Trick" the system, but I'd rather just make the system work with LEDs rather than have a unit burn off power and heat unnecessarily. Any help is appreciated.:up:

[AlarmedBread]

side markers aren't included in the check relay (atleast on my car...) You only have to worry about the turn signals/stop lights. The check circuit wires are black w/ green stripe, you simply have to connect these.

For the front I used a resistor on the turn signal wire for each bulb, it's only hot when turning so I was lazy and went no further.

[DaveSmed]

Sweet, I was hoping you would chime in here or e30tech due to your knowledge of the check relay. To answer your question, the front is run with relays... one for each side. The parking light and the turn signal wires are run across the coil so that the lights act as both parking lights and turns without hyperblinking. There isn't any incandescent bulb fitted into the front, sidemarker, or rear sockets. Is there a way to short the check relay or bypass it entirely so that it doesn't interfere with the lighting circuit? I replaced the flasher unit (under column) with an LED friendly unit and get the same result as before. I bought a 6ohm 50w resistor for each side to "Trick" the system, but I'd rather just make the system work with LEDs rather than have a unit burn off power and heat unnecessarily. Any help is appreciated.:up:

Ah ok, makes more sense now. The relay is a quite creative way for dealing with that, and works very well......except when LEDS are involved.

How the relay you installed and blinking sidemarker mods work is they use the non-illuminated circuit as a ground path, figuring the filaments of 2-3 larger bulbs will act as a sufficient pathway to ground for a sidemarker light or in your case a relay. This setup works very well with normal bulbs, but you now have low current diodes. This same problem affects many auto manufacturers stock cruise control systems, as they use the same idea (seeing a ground signal) through the third brake light on cars where the other two brake lights serve as brake/turn indicators. That third brake light burns out, no more cruise control.

Back to what is happening with your car. That relay up front is managing to flow enough current to light up the tiny bulb behind that little green arrow. Its prob not at full brightness but with the series circuit you have now, its enough to get it to light.

Solution? Diodes. Silicon diodes have a voltage drop of close to a volt, so tossing a few of them in series on the parking light wire up front will allow you to adjust for a desired brightness. If it is taking a LOT of diodes, perhaps lighting up only a row or two through the diodes for parking lights will produce nice results. (I can't say either way, never tried!) Also, don't forget one diode on the turn signal side for isolation purposes, to keep the modified voltage from backtracking through the circuit and lighting other stuff up.

Bonus: Now your light will be % 100 solid state!

[DaveSmed]

Hmm. Just read your other thread and saw you prefer the full bright park lights. I have a ugly solution at the moment, but I'll see if I cant come up with something more elegant. (I hate needing a separate +12 supply)

Relay 1       Relay 2       Relay 3
85:  Park      85:  L Turn    85:  R Turn
86:  Ground    86:  Ground    86:  Ground
30:  +12v      30:  LF Light  30:  RF Light
87:  Relay 2+3 87:  Relay 1+3 87:  Relay 1+2
87a: Relay 2+3 87a: Relay 1+3 87a: Relay 1+2

All of the 87s connect to each other and all of the 87a connect to each other. I would figure a good spot for it is under the fuse box, everything you need is right there. I dislike this solution though as it eliminates the factory fuse protecting the wire to the lights (unless you splice into it in the fuse box, which would be a good move) and the design just seems kludgy to me. I'm picky though. ;) I'll keep thinking.....


Edit: Oh yea, when can we expect a 5W Luxeon array in a high beam? :D

[StereoInstaller1]

I think it is a shame that the BMW manual just shows a box called "Solid State", no actual tech info.

[Schnitzer318is]

^3 relays would be a solid solution, if not somewhat noisy one. LOL but since I am running the 2 up front currently... adding another couldn't hurt. Right now I have it running with 2 12ohm 25 watt resistors per side. The turn signal bulb and the parking light bulb each need a simulated load. This corrects all problems and makes it work as from the factory, but with the LEDs. I don't like having 4 resistors in the trunk though I am not worried about fire issues, I just don't like burning power and heat simply for the sake of doing it.

I had considered the diode route, and then bought an LED controller (SHO Me) which is typically found on ambulances (another solid state solution). This would do the dimmer parking lights and brighter flash... as well as dimmer parking lights and brighter brake lights. But after seeing the LEDs in the daytime I really prefer the brighter setting all the time. Too bad too, because the ShowMe unit was pretty neat and has a built in wig wag flasher too that I could turn on for sh%ts and giggles. What do you think? Should I give it a shot and ditch the relays I have in there now? I might still have to do the resistors or your 3 relay solution, but could ditch the 2 I'm running now. I hooked it up on the bench and it was pretty damn sweet. This is the product: Show Me LED Flasher Unit PDF File

Give me your opinions and suggestions... I'm not in a hurry to finish this as I want it done right, and don't mind taking the time to explore all options. Thanks again for the input so far and to come.

[Schnitzer318is]

Forgot to mention... it's the second one on that list. SHO-ME 11.1005.STT LED LED Flasher (STT)

[DaveSmed]

My two cents? That flasher looks awesome! And it will let you do exactly what you want too, think along the lines of LED brake light/turn signal configuration with the brake light lead wired to the parking lights.

[Schnitzer318is]

think along the lines of LED brake light/turn signal configuration with the brake light lead wired to the parking lights.

I was thinking along these lines as well, but ran into a problem. I have amber lenses behind my red paint... so I installed amber LEDs. Had I a set of OEM all reds I could have done all red LEDs and had one massive set of brake/signal/turn lights. It would have been awesome. Maybe I'll make another set after I get a set of all reds. As it sits now... I am going to run signal lights regular style since they are amber. Wire the output of the flasher to the brake light LEDs which will run as parking lights and brake lights. Also I am going to add LEDs where the euro fog and the area above the reverse light are for extra madness while braking. If I get rear ended I am suing somebody :) I still have to play with it on the bench to get my final setup.

I have completed the LED brake light board using 36 8mm 45,000mcd reds (it's ludicrous bright) and will now start work on the parking light board. I took a video of the flashers in action which I will post later tonight/tomorrow.

[DaveSmed]

Hmm. Well, I have a solution, and it will work beautifully I might add, but a little bit of hunting is involved.

To get this to work, you need to find Splices 210 and 211. They are located in that harness that runs along the bottom of the drivers door to the back of the car. I can narrow it down to in between the middle of the drivers seat (where the harness forks) and the front kick panel speaker. Alternately, you could work at the speaker instead if you wish (probably a little easier)

If you do decide to work at the speaker, in that harness that runs along the door there will be 4 blue/red and 4 blue/black wires. The colors are for each side. The four wires come from the front turn signal, the dash indicator light, the hazard switch, and the turn signal switch. At the splice there is a fifth wire, obviously for the rear turn signal.

What I would do is use a meter and determine which wire is which, and connect the wires with the rear turn signals (any/all of the wires running to the back will do) connected to the dash indicators. The hazard switch and the turn signal switch wires connected together, and wire up the flasher so that the left and right outputs directly connect to the front lights, and to a relay (one for each side) on terminal 30.

Wire up the brake input to the parking light switch. (easy since it's right there!) Connect pin 87 of those relays to the dash indicator/rear turn signal wires. Connect the hazard/turn signal switch wires to the left/right inputs of the flasher and to the relays coil (pin 85 for those following along at home on building a badass turn signal setup) through a pair of diodes. Ground the other side of the coils.

Now, grab a fog light switch (your lacking factory fogs correct? If not next to the hazard button would work for a 2nd fog light button) and connect it to two more diodes to the coils of the left and right relays, and to the strobe wire of the flasher.

Crowning touch? Use a relay to switch the polarity of the white wire under the column that goes to the high beam relay, and connect the relay to the strobe selection wire.


Net result? %100 factory look, strobe feature using all four turn signals with pattern selectable by flashing the high beams, full bright front park lights, isolated rear (turn and strobe only), and the dash arrows indicate strobe pattern. Fucking sweet.

Downsides: Strobes stop with the parking lights on and go solid. If you want, tossing in a relay to break the park light wire (well, stop light wire) when the dash button is pushed will fix it.

Also, don't forget to jump out the factory flasher!

[Schnitzer318is]

I like the concept and followed about 50% of it. Lost me about half way. Would need a diagram, but definitely interested in this wiring scheme. I think I will try and draw one out based on your instructions as I am trying to visualize the diagram in my head and it just leaves me confused. Right now I have everything working, minus the strobes, but using the 2 gay resistors per side. I couldn't resist putting it on the car to see what it looks like. I am really happy with the result.

[DaveSmed]

Hmm, my diagrams usually make sense to no one but me, but I'll try and describe what does what a little differently, maybe that will do....

Lets start with the two relays. There purpose is to isolate the rear signals and dash indicators from the front and the flasher (as the front lights are directly connected to the flasher) unless you are signaling or strobing.

To do that and have it look right, we need to use two relays and keep them controlled separately for left and right, because if wired together, when you went to signal say a right turn with the parking lights on, the left rear light would pop on solid and the right would flash due to both rear lights being connected to the fronts. Now for strobing action, you want both rear lights connected to the front for maximum blinky goodness. :-) That is done via the dash button which also applies power to the strobe wire while were at it. Four diodes, two per relay are added to keep the strobe control circuit and turn signal circuits isolated from each other.

Speaking of the strobe circuit, you can add in a relay if you want to disconnect the parking light wire (well, stop input) from the flasher when the strobe button is pushed. Your flasher sees the stop signal as a higher priority than strobe, so when you would turn on the strobes with the parking lights on, the flasher would ignore the strobe input and all four lights would be on solid.

For changing the strobe pattern, the flasher wants to see +12 applied to a wire momentarily. I happen to think changing strobe pattern by flashing the high beams would be neat, but BMW uses a switched ground from the column switch to control the high beam relay. Easy fix though, pin 85 to the white wire under the column that controls the high beam relay, pin 86 and 30 connect to your strobe circuit (a handy source of +12v, and it also means one less thing clicking when your not using the strobes) and pin 87 to the strobe pattern select wire.


Hope that helps, I was in a bit of a rush the other night so I didn't get a chance to write out the "why" of the way I came up with, which I find really makes a difference. Hopefully that cleared it up. If not let me know!

[Schnitzer318is]

Dave, you rock. That helped a bunch. I got most of it, but was uncertain about the diode placement/resoning. Got it now. I will give this a shot after completing the tails 100%. I'm all giddy about ditching the resistors. Thanks again. :) Will keep you updated.