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Posted by: Qarl Oct 18 2004, 09:05 PM

It seems that the LED lights have a small problem when used with flasher controlled idiot lights (like the turn signal indicator or the emergency brake indicator).

The system doesn't recognize that the bulb is there since the LED uses such low voltage.

I am going to figure out a way to place a resistor across the bulb to simulate the load of the bulb.

I will let you know what I find out.

Regards,

Qarl

P.S. Engineering has been a bit of a challenge as I don't really have a car that is functioning....

Posted by: Demick Oct 18 2004, 10:43 PM

I checked my instruments, and many of my indicator lights use a different bulb anyway - so the LED ones won't fit.

Besides, I don't see muvh value in using LED bulbs for the idiot lights and indicators. The regular bulbs work fine (and are rarely on anyway) and since most are already colored you can't easily change the color even if you wanted to.

So I am just going to replace the instrument backlight bulbs with the LED versions and leave all of the indicator bulbs as-is.

Demick

Posted by: Qarl Oct 18 2004, 11:05 PM

I think the solution is going to be to place a 100 ohm resistor across the bulb. Connect one end to the positive lead and the other end to ground.

The stock bulb is 2 watts.

My multimeter isn't working and I can't measure the resistance of the LED bulb. (If I even can measure it... since it is a diode). I've never understood diodes.

Posted by: sechszylinder Oct 19 2004, 01:33 AM

just another idea : you can use a bulb as the resistor across the led-bulb

just kidding ...

Benno

Posted by: bondo Oct 19 2004, 01:37 AM

To measure the effective resistance of the LED bulb you'd need to power it and measure the current. but it doesn't really matter, rounding it to zero will probably work fine. I bet either of those resistances will work, they may just alter the flash rate slightly.

Posted by: bob91403 Oct 19 2004, 02:55 AM

Gee, thanks a whole lot! I put mine in as soon as I got them. E brake works OK. Turn signals don't. It's nice to know there's nothing wrong with my car. Now I just have to go back and put the old bulbs back in. FPITA. It would have been nice if you had checked this, before I bought bulbs that I now have no use for. I didn't want to ask about the problem. I figured that, soon enough, there would be some mention of this problem if everyone else was experiencing it. I like the lamps. Thanks. As for your research and possible solutions,

Posted by: Qarl Oct 19 2004, 07:27 AM

Try 100 ohm resistor across the bulb... 2 watts. Either get four 1/2 watt resistors at radio shack, or find a 2 watt resistor at an electronics place.

I will be making a solution available. Previous purchasers can get it at my cost, or I will post the simple plans.

One end of the resistor goes to the positive lead of the bulb... the other goes to ground.

Bob91403.... It's hard to engineer this without a working car! :finger2: ™

Be glad I was able to get them friggin made!

Posted by: nein14 Oct 19 2004, 10:04 AM

Karl, you did a great job engineering the LED bulbs for us. I put mine in and they look great! The cost was excellent , don't pay attention assholes that complain about a good deal!!

Posted by: Qarl Oct 19 2004, 12:38 PM

No assholes here... just friends...

Bob's comment was not taken as an offense remark... notice his smiley after he gave me the finger?

The solution is pretty straight forward. I will probably make some plug and play solutions for those that want to use the LEDs for the blinking idiot lights. Cost should be nominal (my hard cost plus S/H).

Regards,

Qarl

Posted by: bob91403 Oct 19 2004, 02:44 PM

No offense meant. I just don't think the solution is worth the trouble. Too easy to just put the regular bulbs back in the turn signals. I have a lot of spares now. Did some people have trouble with the Ebrake? Mine worked fine. For all your OTHER led lamps go to http://www.superbrightleds.com. About $100, to do the rest of the car. Thanks again, Qarl, they look great. nein14

Posted by: TimT Oct 19 2004, 03:05 PM

Qarl does this help?

http://www.buytruckstuff.com/product.asp?selcategory=2&p_gpID=198

Posted by: bondo Oct 19 2004, 03:38 PM

There is still a benefit to using the LEDs for the trun signal indicator. If the bulb burns out the trun signals will quit working. The LED/resistor will never burn out, leaving you with more reliable turn signals.

Posted by: bob91403 Oct 19 2004, 04:11 PM

The bulbs I took out are over 30yrs old. They may have dimmed a little, and gone a little more yellow, but they still work. It's hard to make it "more" reliable than that. Five minutes, a screwdriver, and all these spare bulbs. I don't think I have to worry about burned out bulbs. I'll let my great grandson change them. Nice bright surrounds again. The rest doesn't matter. LEDs are nice because of their longevity, but you won't need them in your coffin.

Posted by: James Adams Oct 19 2004, 06:52 PM

OK, I hooked up a pot across the bulbs, and the turn signal flasher starts working with 90K ohms across the bulb.

The brake flasher needs more current and everything I had to test with was too low of wattage, but it works fine with the original bulb back in line (of course). So Qarl's solution of 100 ohm 2 watt resistor or equivalent should work fine.

Posted by: jgullock Oct 20 2004, 05:39 AM

Can also change to an electronic flasher relay/cube/whatever.

http://faq.auto.light.tripod.com/signal-leds.htm