getting ready to do my climate control Options

[Zimluura]

i'm getting ready to do my climate control in blue leds.

i'm thinking that for *each* of the 3 special toyota bulbs in the unit i can maybe put in 3 leds in a series cluster with a resistor (so 9x 5mm leds providing backlighting and 9x 3mm leds for each active button indicator). does anyone know what voltage those special bulbs normally get. i'm sorta assuming 12v is safe (though my voltmet4er says my cig lighter is 14v).

at 12v my resistor calculations...
http://metku.net/index.html?sect=view&n=1&...dcalc/index_eng
...are telling me a 68ohm resistor for each cluster is the way to go.

i've got a little bit of experience with electronics. but mostly just replacing leds that are already in there. does this raise any red flags for anyone? does it sound like a good idea (to improve light dispersion)?

also i don't know much about power ratings, but i'm assuming that everything is fine if the power rating of the resistor is greater that what the led calculator says the circuit requires. can anyone tell me if this is an accurate assumption?

thanks in advance

[ILuvMyCelica95]

what about the LEDs they make now that dont need resistors, they have the 12v already? Electronics is not my thing but i thought they made these now?

[snadman]

Maybe they do make those, but most I see like that are because the resistor is a variable resistor built in to the power source...and they are specially made for accent lighting in cars...such as those stupid leds kids put all over their cars. The variable resistor is built in to the cigarette lighter adapter.

[Zimluura]

what about the LEDs they make now that dont need resistors, they have the 12v already?  Electronics is not my thing but i thought they made these now?
[right][snapback]330093[/snapback][/right]

well there are prefabricated replacement leds (with resistors aready soldered on) for standard bulb sizes (194, 74).
http://autolumination.com/
i did that for my guages, cig lighter and keyring. but our climate control back lighting uses special toyota bulbs. still might be able to get 74s to fit in there. but this other approach could mean better backlighting without changing anything but the climate unit.

[DmVinny]

i'm getting ready to do my climate control in blue leds.

i'm thinking that for *each* of the 3 special toyota bulbs in the unit i can maybe put in 3 leds in a series cluster with a resistor (so 9x 5mm leds providing backlighting and 9x 3mm leds for each active button indicator).  does anyone know what voltage those special bulbs normally get.  i'm sorta assuming 12v is safe (though my voltmet4er says my cig lighter is 14v).

at 12v my resistor calculations...
http://metku.net/index.html?sect=view&n=1&...dcalc/index_eng
...are telling me a 68ohm resistor for each cluster is the way to go.

i've got a little bit of experience with electronics. but mostly just replacing leds that are already in there.  does this raise any red flags for anyone?  does it sound like a good idea (to improve light dispersion)?

also i don't know much about power ratings, but i'm assuming that everything is fine if the power rating of the resistor is greater that what the led calculator says the circuit requires.  can anyone tell me if this is an accurate assumption?

thanks in advance
[right][snapback]330076[/snapback][/right]

If you use a higher ohm resistor the light will just shine dimmer, 68ohm's will give exactly what the LED calls for in order to give maximum light, anything higher will drop it to a lower voltage giving you less light.

What you should do is calculate all the LED's you are going to use, add them up than calculate what resistor you need for all. So all u need is 1 resistor


This post has been edited by DmVinny: Sep 2, 2005 - 5:30 PM

[Zimluura]

i was thinking of replacing each bulb with a series of 3x 5mm leds (bent outwards to help light dispersion) and a resistor.

as for indicator lights i was going to just go with a 3mm blue for each (so 9 more leds, but in 3mm instead of 5mm).

DmVinny most of my pre-planning has come directly from your site, so your take on this idea means allot. think it sounds like a good plan? think i'll have the space in there to do the led clusters? or maybe should i spread each one out with wire so the leds are really spread across the unit?

don't worry, i wouldn't think of holding you responsible if your advice lead me astray.

[Zimluura]

whew, what a night. swapping the leds was easy, but i did that a week ago. getting the back-lighting close to correct was a total killer. we shorted out one of the lines because of a slip with a voltmeter. so then we repaired it, and fumbled around with thc3 leds and massive 1watt resistors, which didn't work well.

ended up using just one of the light sockets as solder pads, hooking up a 68ohm,0.25W resistor in series with 3x 5mm blue leds. and just aranged them the way the bulbs were. looks pretty good, all told. check my profile for a pic of the whole dash. the ac (and of course rear-window defrost) don't have illuminated labels.

i've become a master at getting the climate control unit out of the car. and i have tons of photos. thinking about trying to put together an html howto, just on getting it out of the car. 'cause after that the correct course of action varies with your preference.