HVAC Leds (any Color)

[cherrington17]

HVAC Leds (any Color)
Parts required:
Soldering gun, solder, Solder flux, Desoldering wick, small tool to pry with (small screwdriver will work), small tool to scratch with (small screwdriver will work here too), 7mm socket, needle nose pliers, 4x270ohm 1/2W resistors. (very important that you get this exact value)

Step 1: Remove shift bezel and radio bezel. Disconnect the wire harnesses and HVAC hoses
Step 2: Remove the HVAC controls. 4x7mm screws (one in each corner) [Ignore the blue circle for now]
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0856.jpg

Step 3: Remove the knobs from the front, and unclip the black plastic on the front, and back. ( I don't have the knobs removed in the pic below)

http://i178.photobucket.com/albums/w246/cherrington17/2009-09-12182755.jpg
http://i178.photobucket.com/albums/w246/cherrington17/2009-09-12182559.jpg

Step 4: Pop the circuit board out of its retainer. It shouldn’t take much, so if it’s being stubborn, don’t force it. Pry lightly somewhere else.
http://i178.photobucket.com/albums/w246/cherrington17/2009-09-12182932.jpg

Step 5: IMPORTANT. See that white wire clip that’s under my finger? DO NOT PULL THIS OUT LIKE I DID!!!! This isn’t supposed to come off like this. Turn the unit over, and pry the white clip (circled in blue) back, while pushing the two white holes inward. It should push that whole module out through the front. I thought that white wire clip just pulled off… it did… it pulled right off the circuit board. If you do this, you must resolder the wires TO THE BOARD. It’s not hard, but it’s unnecessary.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0856.jpg

Step 6: Carefully place the circuit board down, and examine the bulbs. Note where they are, and where their contacts are on the other side. I have them circled in red.
http://i178.photobucket.com/albums/w246/cherrington17/2009-09-12182431.jpg

http://i178.photobucket.com/albums/w246/cherrington17/CIMG0837.jpg
http://i178.photobucket.com/albums/w246/cherrington17/toplefttwo.jpg
http://i178.photobucket.com/albums/w246/cherrington17/bottomlefttwo.jpg

Step 7: Heat the soldering iron, and begin removing the old bulbs. BE VERY CAREFUL WHEN WORKING WITH CIRCUIT BOARDS!! See all those little solder joints around? Yes? DO NOT TOUCH THEM. If you join any of the solder spots on the board, things won’t work. Important things.
You can remove the bulbs by heating the back of the contacts, and prying on the front with the needle nose pliers. Don’t squeeze too hard, the bulbs are glass, and they will break. Once the solder is hot, they pull out very easily.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0845.jpg

Step 8: Use the desoldering wick to remove the solder from where the bulbs used to be. You will know your done, when you have 2 empty holes like I do. If its sealed over with solder, you didn’t remove enough yet. If you did remove a bunch, and there’s still a little solder “cap” on it… just hit that spot with the soldering gun and try to persuade the solder to each side of the hole. Most of the time it will open itself up. Again, BE VERY CAREFUL TO ONLY DO ONE AT A TIME, WITHOUT TOUCHING ANY OTHER POINTS ON THE BOARD. Also DO NOT HOLD THE SOLDERING IRON ON THE BOARD FOR A LOOONNG TIME. All those light green lines are “traces” they have copper under them and spread power from one spot to another. If they get too warm, they will detach from the board. If this happens, congrats, you fubared it. Get another and try again.
Step 9. Insert leds from the front. POLARITY IS VERY IMPORTANT. If you numbered the lights 1-8; the top 4 left to right, 1-4; the bottom 4 left to right, 5-8 the polarities would apply as such… (THIS IS LABELLING IS AS IF YOU WERE LOOKING AT THE BACK OF THE CIRCUIT BOARD, NOT THE FRONT!)
1 2 3 4
- - + +
+ + - -
5 6 7 8
+ + + -
- - - +

So... 2 pictures up... the 4 holes shown, the top two are negative and the bottom two are positive. They line up vertically. The first negative and the first postive are for bulb #1. The second two holes are for bulb #2... and so on.


All the holes are top and bottom. It will be up to you to determine which side of the leds is positive and which is negative. Positive is the Hot, or 12v wire. Negative is the ground.

Step 10: Place solder flux around the opening of each led, on the back of the circuit board. This step will greatly assist soldering them in place. Even if your solder has flux already in it, use extra around each lead, on each led. Now put a bead of solder on the tip of your iron, and touch the base of each lead, as it touches the circuit board. The flux will pull the solder into place, on the board, around the lead (number 1s in picture). DO NOT TOUCH THE OTHER LEAD OF THE LED. Do one at a time, be very careful. YOU NEED A GAP BETWEEN THE TWO CONTACTS(number 2 in picture below). If you use too much solder, you will join the power and ground, and prevent these from lighting. Not just one, ALL OF THEM.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0849.jpg

Step 11: Trim the extra leads off the leds. (do not leave it like the picture below)
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0846.jpg

Step 12: Take the 4 resistors, twist the ends together, so they are in a cluster, and solder the ends. What you just produced is one resistor with a 70ohm resistance @ 2Watts. This is MANDATORY.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0853.jpg


Optional Step, But important Note. TEST BEFORE MOUNTING. It’s important to test each led before you attempt this, you don’t want to get this far before finding out one led is bad… thus making all of them explode. In order to test this, you need a 12V power supply, with your big resistor on one of the test leads. It doesn’t matter which one, just one of them. On the front of the circuit board, you can see the Pins where the connector attaches. (12 pins in 2 rows) On the front, there is a letter in each corner of the little box of pins. The letter you’re looking for is G. The power for the lights, in 3 pins inward, from G. The ground is the pin immediately next to this, farther from G.
G * *(+)(-) * *
Touch your power lead to the power pin, touch your ground to the ground pin. (WITH THE RESISTOR) and you should have 8 lit leds. If you don’t, you did something wrong, go back, and do it again. If they get uber bright, and explode… you did something wrong, go back and do it again (with new leds)
Step 13: Reassemble unit, Scratch off the blue film from the inside of the HVAC controls if you need to.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0858.jpg

Step 14: Mount unit
Step 15: Find the gray wire on the harness, Cut it, and solder your big resistor in line with it. Heatshrink it back together, and give it some electrical tape for good measure.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0854.jpg

Step 16: Wait for darkness, and kick on your lights. Admire your new colors. :thumb: Your done.
http://i178.photobucket.com/albums/w246/cherrington17/CIMG0868.jpg

Incase you wanted to know… math for the resistor:
8 Leds @ 0.020A = 0.16A
13.8V(operating Voltage) – 3.6V (led forward voltage) = 10.2V
10.2V/0.16A = 63.75 Ohm ~70 Ohm

12V*0.16A = 1.92W ~2.0 Watts
Therefore, You need 70 Ohm @ 2 Watts

.... to get 2 Watts, you need 4x 1/2W resistors in parallel… so….

4x70ohms = 280 Ohm. Closest common resistor is 270 Ohm.

270/4=67.5 Ohm @ 2 Watts.
The reason for all the ~ (approximate values) is because all resistors have a tolerance. Most common is 5%.

I calculated this for my white ones (3.6) (which share voltage rating with blue and UV) and then again for the red/yellow/orange, and the resistance remains the same, when you take the 5% tolerance into account.

[lonnie]

Very good write up! Whats the time involved?

[cherrington17]

If anyone can't figure this out now... I'll personally hit you in the face with a tack hammer... I made this as thoughtless as possible


Time: 3hrs taking your very sweet time

Skill level: Moderate to easy. If you know how to solder, its cake. If you don't, it'll be a little tricky.

[Ryan from Ohio]

excellent!

I have some LEDs burned out or very very very weak... Its the ones for the push buttons in my case.

One question about the resistors... Why? Why do you need the resistors but the stock ones didnt?

So what colors did you use and how many LEDs total?

Get us the Rat Shack part numbers! lol

Im going to do this, tomorrow!

[cherrington17]

8 leds. I used white. (skimmer!)

resistors Part number : 271.1112 (comes in a pack of 5 for $0.99)

The stock bulbs are halogen, they run on 12V. Leds do not... so you need resistors.

[Ryan from Ohio]

And the last thing...

Looks like you missed 4 of them on the buttons?

You have the actual buttons, my A/C one isnt bright at all... cant tell if its on or off...

http://i38.photobucket.com/albums/e136/basstronics/2009-09-12182431.jpg

[cherrington17]

those green circled ones weren't touched in this mod. I have no idea about them.

I know they are leds(stock), but unknown voltage, or type.

[Chipmunk-Alero]

The only thing I dont understand is which way you put the leds in the top and bottom holes on the board. Is the top hole + or -. Or does it even matter? I just figured put the long lead through the top hole and the short lead through the bottom hole. Please explain or correct me.

[cherrington17]

reread step 8. I tell you what the holes are, you need to know what lead is + and what lead is - for the leds your using.

[Chipmunk-Alero]

Ok, I got it now, I might have to look into this.

Also, where you say heatshrink the resistor in-line with the gray wire, you mean cut it, strip it, twist it, solder it, tape it, right or something else?

[Ryan from Ohio]

yes. You will need to physically cut that line in half and place the resistors in line with it.

Are the lens in the cover over it colored? Or is this something we can overcome you think?

[cherrington17]

Are the lens in the cover over it colored? Or is this something we can overcome you think?

i don't know what your referring to... is what lens cover colored?

[Ryan from Ohio]

i don't know what your referring to... is what lens cover colored?

This part:

http://i178.photobucket.com/albums/w246/cherrington17/CIMG0858.jpg

So trying to make the already blue/red colors into something different would be interesting...

[cherrington17]

i didn't bother with that, since i want it to stay red/blue.

by the looks of it, its a white film on the back, and colored on the front. so.. you could scratch the front off, and leave the white film... BUT i'm not sure how you'd go about having mixed colors then. Maybe mount two leds on the back, at the base of the arch, in different colors, pointing them toward the middle.

i don't know.

[hok666]

:thumb: nice write up Ill be doing this on my spares for practice :thumb:

[cherrington17]

Bad news... The buttons at the bottom... that lit up blue in my pics...

yeah... they ENTIRE ASSEMBLY is blue plastic. Nothing to scratch off. Gotta live with it, or find out if other models have clear ones with a coating.

[Ryan from Ohio]

I bought the stuff to do it, now to just DO IT... lol

[Ryan from Ohio]

Ok I know its been some time, but Im finally doing this. I waited until I was switching out my HU.

My main reason here was my A/C button light was out.

After getting it all apart the buttons lights are 3 green 5mm LED's. The Defrost is smaller LED (orange). The rest as Chris pointed out are bulbs.

I will be switching them ALL out except the small orange one.

Also not the clip circled in blue is a real SOB! I pried it out and it snapped off... The plastic is brittle, you would be better off de-soldering the connection at the white plug.

Of course if your doing this project you need to have the proper Soldering Iron. Im using a Weller WLC-100 w.062" tip. Im using Chemwik de-soldering braid as the Rat Shack stuff is worthless crap.

If anyone wants this mod done but doesnt have the equipment I will do it for a nominal fee.

[Ryan from Ohio]

And to just note this isnt an job for someone who isnt good with soldering. Heck I thought I was fairly good and I just broke a trace. Now I have to repair it. Argh. Wont be bad though, just amp going to add a jumper wire in its place.

[Ryan from Ohio]

Ok all done, tested and fully installed.

Its nice and bright now, thats for damned sure.

The buttons for fresh, recycle, A/C and defrost are LEDs. My A/C was burned out, now its perfect!

If you replace these make SURE you note which side is + and -. I didnt and had to look at Chris's pictures CLOSELY, and then follow traces... I got lucky.

Also note that the LED mounts are a bit different than the bulbs. I ended up breaking two traces and lifting one in this project. I had to run one wire jumper and use the leg of one LED as a jumper.

[cherrington17]

glad my how to helped ya. (i knew that +/- pic would help)

I'll do doing some of these in my free time as well. As soon as I get my HVAC from cactus, I'm making a set for chipmunk with red. To see how it turns out...

ryan, what color did you do? got pics of the finished product?

[Ryan from Ohio]

I used ultra bright 5mm whites for the 8.

I used 3 green ones for the replacements. Im not sure how bright the greens are. All were bought from rat shack.

The how to was good. Whats lacking in the pictures to know whats truly + and -. The one said "two pictures up" and I went 3. Even that was a bit fuzzy.

I would HIGHLY suggest to people letting someone with skill do this.

[cherrington17]

I'll relook at the pics tonight... make sure they are labelled correctly...

and yes, if you have a really hot soldering iron, or hold it on the circuit board too long.. you will pull up traces... which is BAD

[Ryan from Ohio]

This is what I got, with a .06 and .19 tips.

http://www.amazon.com/Weller-WLC100-Soldering-Hobbyist-Yourselfer/dp/B000AS28UC

Using the proper solder, flux and wick is key. Have you tried Che-Wik yet? When you do, you wont bother with the other junk...

http://i38.photobucket.com/albums/e136/basstronics/Alero/100_6192.jpg

Best pic I could get.

I noticed some flicker... Im thinking when I did the gray wire my one solder joint wasnt the best...

[cherrington17]

You'll want a 15 or 25 watt soldering gun. I used a 45, and it was WAY too hot.

luckily.. no traces were compromised.

[heineck]

Just finished this mod, and damn blue hvac lights with the transparent knobs are sick as hell

[PappaSmurf]

Al, Cherry, or Ryan,
I am glad that you all have got this mod installed and working. Now I know that one of yall would be willing to do this for me and make some extra cash. I was just wondering which one of you could do it, send me the hvac unit and then wait for MY hvac unit to replace the one you gave me.

I only ask because I am not the best around a soldering gun, unless you want a glob of silver stuff covering the whole thing. LOL
-Smurf-

[heineck]

Aye smurf Text me

[heineck]

just thought id thro up a pick with the blue knobs, i have to find the last one, i seem to have misplaced it :p
http://img705.imageshack.us/img705/1650/img00157d.jpg

[cherrington17]

Nice hein-y...looking sweet!

I have a red hvac on standby, for chipmunk. (Swapping hvacs in the winter is crazy) but ryan and hein-y have had good results, id trust either of them to do it properly. Its easier then it looks. (Espicially w. The idiot proof write up. :lol: )

[heineck]

yea i went sorta LED crazy this weekend did the vents, hvac and floors

[AleroDrime]

hey guys my leds have a long stem and a short one, which is positive?

[colonel6632]

long stems are normally positive. but not always. just hook it up to a battery and find out

[Chris2000]

hey guys my leds have a long stem and a short one, which is positive?

Apparently you have never heard of google or any other type of "search" engines.

long = +
short = -

[heineck]

long stems are normally positive. but not always. just hook it up to a battery and find out

If he does that without a resistor it'll get really bright and then pop.

X2 @ the google it takes longer to log on here and post then to just google it

[colonel6632]

i used a 1.5 volt battery. i didn't mean the car battery. guess i should of been more specific

[heineck]

o ok i use 9 volts, and i tried that without a resistor and pop! one less LED

[cherrington17]

o ok i use 9 volts, and i tried that without a resistor and pop! one less LED

yup.

button cell batteries, or a 2 pack of AA/AAAs work well as testers. OR (with resistors) a 12V power supply.

[AleroDrime]

i did google and went ahead and soldered, i wish i had somthing to test it off of, down side of soldering in your dorm room,

ive got to go back and resolder 3, i had one place where the copper lead came up, but not form the heat, from putting the led through so i soldered the copper part to the led very carefully, itll be interesting if that works, if not its a negative and i think i can coppy what ryan did and make it work

[heineck]

well go out to ur car and plug in the harness directly to the board, but dont forget to do the inline resistor or ur just gunna blow em all up

[Weazel]

Cool write up! Do more neat LED tutorials and you'll be my official hero.

[cherrington17]

Cool write up! Do more neat LED tutorials and you'll be my official hero.

Check the link in my sig... all the links to my led how-tos in there.

[Weazel]

I'm simply oblivious. I've been on that thread a few times now haha

[AleroDrime]

does the orientation of the resistor matter? Should the red or gold end be towards the controls

[Kilroy]

does the orientation of the resistor matter? Should the red or gold end be towards the controls

It depends on whether or not you have an ac or a dc resistor.;)

[cherrington17]

drime, the resistor doesn't matter. diodes have polarity, resistors don't.

(kilroy, i'm positive he doesn't have AC resistors)

[PappaSmurf]

Cherry,
Who knows with this kid? LMAO
-Smurf-

[Alerojester]

:haha: i second that... :lol:

[heineck]

I third it...

[alerogls001]

I can vouch for Heineck- just got a set he made me and it looks awesome. :). If you're unsure about it or don't have the time then contact him.

[heineck]

thank you

[joshkrdr]

Hey cherrington, how many led's did you use in the HVAC? Did you just replace the existing lights or add more? Also, what degree range led's did you put in?

[heineck]

dood, see 1st post

[joshkrdr]

Yep I just joined

[joshkrdr]

ok well i guess i'll just solve the problem by adding more led's in the dark spots b/c those are only 30...

[cherrington17]

I used standard 5mm leds. (not sure about the angle. look it up on the tech page for leds on www.oznium.com)

If they aren't wide angle enough, sand the tips down. And I only replaced the bulbs that were in there. removed the halogens and replaced with leds

[joshkrdr]

ok that works, bc i used 3mm and the blue's have some hot spots so i added a couple more to try and fix it.. I'll try sanding them down a bit and see if that helps. Thanks i appreciate it

[03Sleepr]

anyone got pics of a red HVAC yet?

[cherrington17]

I have one sitting on my desk. I'll go get pics and update.

[cherrington17]

Red:
(this unit is actually for sale. The "hot spots" will be sanded and gotten rid of)


The blue for the AC temp doesn't seem to light up at all, nor do the indicator hash marks on the knobs. The bottom switches are all red, not purple (as originally thought they would be)

[03Sleepr]

thanks, I wanted to see how the indicator switches look..I'll give mine a try within the next week or so and if my HVAC is bad or I cant get it the way I want it I'll probably buy this one if you havent sold it

[cherrington17]

Chipmunk was suppose to buy it... but never followed through. (i'm sure theres a reason, i never followed through to try to pressure him to get it) :lol:

So its sitting on my desk... first come first served.

[03Sleepr]

how much shipped to 67042?