LED TAIL light conversion, a way to DISABLE stop lamp warning?

[chinaonnitrous]

so, ive done a simple LED conversion in a friends Civic taillights, using about 20934802398402934832 LED's, circuit board, resistors etc.......

Now, I want to try this on a Q45, perhaps using the Crystal taillights, but is there a way to actually disable/Bypass/Fool the Stop Lamp warning system?

As annoying as it is now, I imagine it would freak out with LED"s back there.

[elwesso]

if you wire it right, it wont effect it..... I hooked my LED's right up and it didnt do anything...

[Q451990]

It would definately freak out. I tried some plug-n-play LEDs from http://www.tmiled.com and although they looked great the warning came on.

The sensor in the trunk senses the current draw from the bulbs, and depending on what it senses - either sends ground or nothing to the ECU. Ground the wire to the ECU and you're done...

Heath

[elwesso]

if you wire the LED's in groups it will work fine... Used 3 volt LED, wire them in groups of 4 (so that each group draws 12 volts) and then wire the groups together.....

[Q451990]

Don't confuse Volts with resistance... Both the LEDs (wired correctly) and bulbs work on 12V, but the bulb has a 21-29W draw, while the LEDs (at least the ones I used have much less... I don't remember the spec. but I want to say maybe 4W?. That's a big difference.

I'm not sure why your car didn't show a warning when you used your LEDs - but I suspect it's been bypassed.

Heath

[chinaonnitrous]

Exactly what I was thinking, theres no way I could wire up enough LEDS to emulate the current draw of thoes bulbs in there now.

Any idea which wire it is? (per FSM?), otherwise I'll poke around with the volt meter.

It would definately freak out. I tried some plug-n-play LEDs from http://www.tmiled.com and although they looked great the warning came on.

The sensor in the trunk senses the current draw from the bulbs, and depending on what it senses - either sends ground or nothing to the ECU. Ground the wire to the ECU and you're done...

Heath

[Q_SHIP]

What about LED turn signals in a y33? Will this screw anything up?

[JebsNYCQ45]

like this?

[JebsNYCQ45]

clear tails

[Q45tech]

Just measure the sensor output voltage [in trunk lip] to the display computer [pins 9&4] and emulate it. Only a couple of choices ground and 12 volts...........see wiring diagram. Fully explained in manual.

[AZhitman]

Jebs, those are SO hot.

[JebsNYCQ45]

Jebs, those are SO hot.

Y THANK YOU VERY MUCH....I FOUND THEM IN JAPAN AFTER ABOUT 3 MONTHS OF LOOKING......ALL I HAVE S THE PICTURE THOUGH

[DrewQ45]

Exactly what I was thinking, theres no way I could wire up enough LEDS to emulate the current draw of thoes bulbs in there now.

Any idea which wire it is? (per FSM?), otherwise I'll poke around with the volt meter.

You need to apply an additional current load on the line to match the total current draw.

Here's my idea....

Measure current draw of stock brake light by hooking up an ammeter in series. Then, measure current of LED setup in the same manner. The difference in amperage (Stock Amps - Led amps) = target current load.

Get two old brake lamp sockets with wires attached from any car..doesn't really matter, what will matter is that the amperage of the bulb will match the target load. .... string the socket in parallell with the Led unit and cover the bulb with foil paper or some other opaque medium that can withstand heat...Hmm, maybe not such a good idea...maybe you can point the light inside toward the trunk where none will be emitted into the lens. The difficulty lies in matching the amperage. Perhaps you may get a bulb who's amperage is actually higher than the target load, then trim by adding a resistor in series on one of the wire leads. Maybe even a small potentiometer (radio shack) would work then you could esentially "dial" in the resistance to effect the proper load... do this with ammeter attached and you'll be right on the money... watch that brake light warning disappear!

...No charge for this advice, just send me a set once you build it...

...Drew...
Modified by DrewQ45 at 8:13 PM 12/8/2005

[chinaonnitrous]

I thought of doing that aslo, by giving the car what it wants to see...but seems like useless work, since ussually the final signal to trip most sensors in cars is usually +12v or a simple ground.

[Q451990]

Rather than using bulbs, why not put a resistor in series? I suspect it would generate quite a bit of heat. The only reason I would do this is if the warning would still work if the LEDs died... otherwise it's just excess voltage draw.

Regarding the LED turn signals... I'm running them on the front. They will cause the flasher to "fast blink" as if a bulb is out - but I replaced it with a solid state one from the same web site.

Heath

[DrewQ45]

Rather than using bulbs, why not put a resistor in series? I suspect it would generate quite a bit of heat. The only reason I would do this is if the warning would still work if the LEDs died... otherwise it's just excess voltage draw.

Regarding the LED turn signals... I'm running them on the front. They will cause the flasher to "fast blink" as if a bulb is out - but I replaced it with a solid state one from the same web site.

Heath

Having just a resistor in series will not generate the current flow you need... Rather it will do quite the opposite and make the problem worse. We're trying to generate conductance...not resistance. Nothing excess about it since it's the lack of current flow that sets off the warning in the first place. I'm sure someone can come up with a better load than a light bulb but it's all I can think of right now. My whole point behind this is to not disable the warning lamp which might save a few tickets $$$. Remember, there is also a flasher relay to deal with.

[q45VIP]

if you wire it right, it wont effect it..... I hooked my LED's right up and it didnt do anything...

Do you have pics you can share with us?

Thanks.

[elwesso]

Patience, grasshopper...

[njcomputerman]

how about a group buy ? Ineed for 1991

[Q451990]

Having just a resistor in series will not generate the current flow you need... Rather it will do quite the opposite and make the problem worse. We're trying to generate conductance...not resistance. Nothing excess about it since it's the lack of current flow that sets off the warning in the first place. I'm sure someone can come up with a better load than a light bulb but it's all I can think of right now. My whole point behind this is to not disable the warning lamp which might save a few tickets $$$. Remember, there is also a flasher relay to deal with.

You're absolutely right... a resistor in series would drop the voltage down. Sorry... I think I meant to say resistor to ground. Wouldn't that creatate a load that, at the right resistance, could simulate a bulb? My understanding of light bulbs is that they're basically resistors that convert electrons into light and heat. A resistor does the same thing, but without the light part...

I'm absolutely with you on finding a way to keep the warning!

Heath

[heywier427]

so has anybody figured this out yet. or have we given up. how do you think a set of clear tails would look with rows of the larger (10mm) leds would look. ive got a set of broked tails so im gonna try. remove orange red lens. keep the plastic light defuser in there and use that to hold the leds. just drill the holes and glue them in place. but before that have the insides chromed, fifty bucks. then cut out a piece of plexi and heat it up till it contours the housing and glue it down. maybe slant the led rows like the g35! my cars pearl so it should contrast. fifty bucks for taillight chroming. spending more time with my Q, priceless...

[lino]

so has anybody figured this out yet. or have we given up. how do you think a set of clear tails would look with rows of the larger (10mm) leds would look. ive got a set of broked tails so im gonna try. remove orange red lens. keep the plastic light defuser in there and use that to hold the leds. just drill the holes and glue them in place. but before that have the insides chromed, fifty bucks. then cut out a piece of plexi and heat it up till it contours the housing and glue it down. maybe slant the led rows like the g35! my cars pearl so it should contrast. fifty bucks for taillight chroming. spending more time with my Q, priceless...

Got an update?

[BlackBirdVQ]

Thanks for all the needed info on the computer light maulfunction idicator

Now I need to make the stupid computer stop saying my headlights are burned out. I fitted a set of HIDs from a 02 RL into my OEM headlights and they draw less amps than stock bulbs do, giving me the message on my computer.

I have been living with the message for over a week now, but the light output of the HIDs is deff worth it.

[heywier427]

yea didnt like the way it came out. i was driving be hind a 94 a week after i made them and decided the kinda dim stock look was right on the money.