Changing the A/C LEDs.
Kindly supplied by Lawrence Ostle.
Disclaimer/Comment – Lawrence Ostle:
This procedure worked for me, but I guess it may not work for you depending on your car, ability and tools you have available to you, so if your car bursts into flames or you have a divorce/nervous breakdown or any other bad event as result of following this tutorial please don’t blame me ;-)
I wrote this tutorial after the fact, so if I missed a few steps - apologies.
I am NOT an electronics technician, and may have got things wrong. However the unit I modified works and was on a test bench for a week without getting hot or anything else odd happening and is in my car now.
Please take this document at face value – I did this for my own pleasure and documented it to give something back to Soarer Central which has been a source of education and fun before and since I bought a Soarer.
The only thing I might have done differently is adding some more diffusing material behind the LCD display. You can just see the outline of the LED’s faintly, but I am being very critical. You may want to add some crunched up clear Glad wrap as a diffusing mechanism or some other material. The LED’s do not heat up, so I would imagine this might work quite well.
LED’s are polarity sensitive, so be aware of this.
LED’s require an appropriate inline resistor on the positive leg or they burn out.
The positive leg of an LED is (usually) the longer of the two
LED’s are about $2 each, so don’t experiment too much!
If in doubt – Google.
I found this quite handy: http://www.luxeonstar.com/resistor-calculator.php
I am not able to quote all sources used in this document but many thanks to those that have gone before.
NOW – on to the job at hand:
What you need is:
- screwdrivers of various sizes, Philips and flat.
- a 10mm socket driver is handy (screwdriver-like tool with a 10mm socket on the end) this is used to remove the bolts on the metal cradle – more about this later
- small side-cutters
- small pin-nose pliers
- a soldering iron
- a hot glue gun
- solder sucker is handy
- a multi meter is good
- a ‘third hand' – literally, and/or one of those crocodile clip ‘gripper units' from Jaycar/Dick Smith/Tandy (hence known as J/DS)
- a 12 volt power supply is of great use for testing the bits as you go – I used an old transformer – this allows you to test in controlled steps before plugging the modified unit into your car and cursing when one LED fails to light up.!
- solder $5
- some thin dual core flex with a trace marking (white line on one core to allow you to distinguish positive from negative) $2
- hot glue sticks $5
- 13 x Jaycar LED 3mm Blue 1000mcd CAT. NO. ZD0130 (Australian reference, www.jaycar.com.au) – around $26, or less if you buy more than 25 if I recall
- 6 x 300 ohm ¼ watt resistors (from J/DS) around 36 cents
- various diameter shrink insulation tubes (from J/DS ) around 50 cents
Around $40 all up
- Some soldering skills and a bit of electronics know how and common sense
- An afternoon undisturbed
- A steady hand
- Patience – don’t rush this
- If you can do the job in stages – all the better
- A workbench and lots of light
- Soothing music
- 2 – 3 power points for simultaneous glue gun/soldering/transformer action!
SECTION 1 – REMOVING A/C CONTROL UNIT
1. Remove the cup holder and set aside. I used the cup holder to store all screws etc for the duration.
2. Remove the two screws inside the cup holder
3. Put the car in neutral
4. Pull down the plastic yoke below the gear knob to reveal the screws holding the gear knob
5. Two screws are revealed, remove these
6. Remove gear knob and set aside
7. Tug the black plastic gear shift surround upwards, it’s only held in place by clips – no screws
8. Remove the connectors that connect the shift surround to the car using the pin nose pliers to carefully squash the release clip and pulling gently at the same time. Set the shift surround aside.
9. Remove all the screws which are now revealed holding the console surround.
10. Remove the console surround by tugging it sharply away from the dash. At this stage there should be clips only holding it in place.
11. Remove the connectors that connect the console surround (a/c, emergency flashers). Set console surround aside.
12. Remove all screws holding the metal air con control cradle from the dash cavity, including the two 10mm bolts (use the driver in the tools list page 1)
13. Partially remove the metal cradle from the dash – it’s not required to remove it completely, just enough to get to the screws on the sides of the a/c control unit.
14. The a/c control unit is fixed in place by two black screws either side, remove these, and prise open the cradle slightly to clear the plastic nipples either side that hold it in position in the cradle.
15. Remove the three white connectors from the rear of the a/c control unit using the pin nose pliers, (squashing the release clip gently as described before)
16. The a/c control unit may then be removed from the cradle
SECTION 2 – DISSASEMBLING THE A/C CONTROL UNIT
1. Looking at the rear of the A/C control unit you can see two small screws which need to be removed
2. The front and the back parts of the A/C control unit may now be separated by inserting a flat screwdriver under the lip between the two sections and gently easing them apart, first the top, holding that open, and then the bottom.
3. There are two connectors linking the back section to the front, one white and one brown (in my case), gently remove these from the front section (this makes it a less crowded working place later).
4. Looking inside the unit you will see a white plastic panel secured by number of screws.
5. Remove all visible screws
6. Prise the black plastic tabs that secure the assembly in the black case outwards on one side of the unit and then the other, while pulling the white interior assembly out.
These tabs are shown below:
7. You will now see the boards that comprise the insides of the unit.
8. The rear white panel with the odd green connector strip may now be removed. This is the panel that provides light to the buttons.
9. There is a flat green cable connecting the rear panel to the rest of the assembly which provides power to the original bulbs
10. Remove the flat green cable from the connector on the side of the LCD board
11. There are two screws connecting the white LCD holder to the board
12. Remove the screws
13. NOTE – the LCD is fragile - do not mess with it or the pins that connect it to the board.
14. You then have the option of bending the LCD unit back in order to remove the light panel located under the LCD or carefully cutting the legs with a pair of side cutters. The latter is the preferred option to avoid damage to the LCD.
15. Cutting the legs of the LCD is not as bad as it may seem. Apparently the bending manoeuvre can create hairline cracks in the LCD which may result in bleeding at a later stage which is expensive, so cutting is recommended!
The legs of LCD panel cut as shown above. I staggered the cuts so they were not side by side in order to provide more space to resolder and avoid shorts across the legs.
At this stage the unit is disassembled, and you can proceed to swap the lights for LED’s
SECTION 3 – CHANGING LIGHTS FOR LED’s
Three sections may be changed
LCD panel back lighting
A/C button illumination (A/C, off, fan level, demister etc)
Function indicators (I didn’t do this but should be easy)
LCD Bulb Replacement
1. Remove the diffuser panel from the light housing. You will see three blue bulbs inside. These are the ones that generate the insipid factory illumination.
2. De-solder the 3 blue bulbs that illuminate the LCD from the rear. You will see two holes for the legs of the bulbs, you will use the holes for the legs of the LED units (next step)
3. Fabricate 3 replacement LED units. This is done by cutting the legs of two LED’s to the appropriate length and soldering them together using the appropriate resistors as shown in the diagram below
4. I used two small LED’s per section pointing sideways to improve the spread of light. IF you face them straight on you will see points of light on the LCD – not a good look!
5. Use heat-shrink to insulate all exposed wires as appropriate during the fabrication, particularly the positive and negative legs.
6. Ensure the heat shrink is of an appropriate length – probably about 6-8mm on the legs.
7. Solder the LED assemblies as shown - observe polarity – red crosses below show the positive pole on the board. This is the rear of the unit below, showing the positive and negative LED assembly leads that have been pushed through the holes from the other side and soldered in place. You may have to simultaneously heat the blob of solder around the hole and push the wires one at a time to get it through the hole
8. Push the wires through as far as you need – you may want to pull the wire through using the pin nose pliers from the back of the board one at a time while heating the hole/solder blob – they are quite flexible and this can be done. This is where an assistant helps – my wife now knows more about soldering than she ever wanted.
9. The further away from the diffuser the LED’s are the better in order to avoid light hot spots, so pull as much of the wire through the hole as you need to – probably up to the base of the heat shrink is a good indicator.
10. Ignore the wire shown in the middle of the picture with the red/pink insulation tubes at this stage as it’s only relevant later, but you want to trim the other leads and leave the centre ones long – more later on this.
8. This is what the unit looks like from the front of the unit (facing the driver) – LED’s pointing sideways, and the legs of the LED assembly poked through the hole in the white plastic housing and then through the board and soldered on the reverse side.
The red bits are heat shrink tubing used for insulation.
All three little LED units in place.
And here it is powered on – tah dah!
9. Put the diffuser back in – you may want to try crumpling up clear Glad wrap into small cylinders and place into the recesses where the LED’s go before replacing the diffuser to make the light fuzzier and avoid light spots on the LCD – give it a try. See how nice it is to check as you go using the 12v power supply? This gives you an immense sense of security. The light is quite strong so don’t be too worried about dulling it too much with additional diffusing.
… And here is the unit with the factory diffuser in place shown below …
10. Put the LCD panel back – it fits back into place quite naturally, and you can proceed to the next step without taping it in place or taking any other steps.
Next, re-solder the legs of the LCD. Once done, check the continuity of the legs with a meter across the join, or by pressing one side of the join gently with a screwdriver, and checking to ensure that the leg on the OTHER side of the join moves too. Try not to apply too much heat during the soldering stage – this damages the LCD too apparently.
11. Insert the two small screws to hold the white plastic LCD assembly in place.
12. The LCD light replacement is complete
Replace the A/C button lighting.
13. Unscrew the existing blue bulbs with the grey bases (they are like domestic bayonet light bulbs, they are not soldered in place) and strip out the green conductor strip. You can discard these.
14. Make up little clusters of 2 x 2 LED’s and 1 x 3 LED’s, using a 300 ohm resistor for each individual unit using the same principles described before. Put these in the holes, and use a small amount of hot glue to hold more or less in place. Trail the tails of the wire through to the reverse side of the board.
Once done join the positive leads together, then join the negative leads together to form a single power lead (positive and negative) as shown at the top of the modified panel below. Use heat-shrink to insulate any exposed wires as appropriate during the fabrication. In this way all three light clusters are powered from one dual core lead.
This lead will take its power from the LCD panel. Move the LED’s into the desired final position, and use hot glue to secure the LED harnesses as shown. Hold in place until cool.
The above shows the placement of the LED clusters – three LED’s on the left, two in the middle and two on the right.
The pictures above show the original panel at the bottom and the modified panel at the top. The left and middle sections of the modified panel consists of two LED’s as described, while the right hand section consists of three LED’s
I pointed the LED’s sideways too, to allow an even spread of light.
I used liberal amounts of hot glue to ‘meld’ the whole lot together. Looks crap, works fine.
15. Route the wire through the slot shown in the second picture below so that it is not pinched between the board and the light holder, then solder the power lead as shown to the middle LCD panel lead shown below – observe polarity. THIS is the one you left long in a previous step. Push the heat-shrink tubing over the exposed metal leads and shrink to size required using a heat gun or judicious application of the hot point of the soldering iron.
At this stage you can test the whole lot by applying 12v to the positive and negative points shown adjacent to the centre red cross below – it should all light up with a cool blue glow. If not, you probably have reversed polarity at some stage – doh!
16. Once done, put the button backlight panel in place and re-insert screws.
17. Reverse the removal procedure to put it all back together and that’s about it.
- In order to ensure that the buttons actually work once the unit is re-installed, all screws must be tight and the black plastic tabs holding the board inside the case are engaged properly – if they’re not the buttons will not be able to apply sufficient pressure to the internal switches. You may want to push the tabs inward to ensure that they are clipped in place well – this caught me out, and some of my buttons did not work properly first time.
- You can test all of this prior to screwing the unit back into the dash, just re-insert the three white plugs at the rear of the unit, switch on the ignition and test away.
- I used blue LED’s, white are also nice – depends on you.
- The end result looks like this (just not fuzzy!) but you get the idea
'94 jzz30 gttl, 2 mini's one supercharged
Hello, I just followed this how-to and found it extremely helpful, thank you Lawrence Ostle.
I thought I'd put some extra info up just for anyone else wondering, as i did my leds a different way which i think would be easier.
To light the control unit you can also use t5 LEDs that screw straight into the button light bulbs and are 12v already so you dont need to use a resistor. I purchased these through ebay for a total of $2.20 per pair (I purchased 6 in SPARK BLUE as I also used these for my lcd lights as well).
One thing i did, was used a drill to just drill slightly into the top of the led to curve it inwards, which when the led is on helps transfer more light sideways which is what you need as the buttons get the light transferred through perspex at the rear of the buttons.
To use these, make sure you check which pin is the positive and negative. This can be done using some wire and a car battery or even some scalectrix or train tracks use a 12v dc so you can use them to power it as well. Once you find which one is positive mark it on the back, I used whiteout.
To install these you simply screw out the original 3 bulbs as shown in the picture under.
Ii also found out which part of the circuit board is the positive - which is the upper half of the circuit board, so you dont have to keep putting the unit back together and test it in the car.
With the lcd backlighting I used the other 3 t5 leds I had purchased.
I simply unwound the led wires out of the holder and unsoldered the original 3 filament bulbs and then soldered the 3 leds in place and tried a few different ways to diffuse the light, as the led by itself worked but had very bright circle in the middle.
In this photo I had 3 leds installed and had the original diffuser and white diffuser (from back of original lcd) fitted.
On the left I just had the plain led, which you can see the very bright centre.
In the middle I had the led, and fitted the blue condom off the original light and also some glad wrap installed. As you can see this spread the light very well you just have to make sure you fold it up and dont have spots that have crunched up too much as you will see dark lines from this.
On the right there is the led which just has the blue condom off the original bulb. This diffuses light better, but still had a bright centre to it.
From this I decided to use the led with the blue condom and glad wrap to diffuse it better.
From this I fitted the new lcd screen following this tutorial and reinstalled my unit back together and fitted it to the car and tested it as shown in this picture.
From this I reinstalled my centre console and tested the whole unit which worked like new again.
in this photo the lcd screen looks blotchy but it was only due to the camera on my phone - it actually looks almost perfect i just wasn't able to get it on my phone sorry.
I hope this is useful to someone and I'd like to thank Lawrence for the tutorial and Rob Rojo for the screen from his group buy.
THAT'S what this forum is all about......
Just to add my own experience in doing this...
The original bulbs can simply be replaced with T5 Neo Wedge LEDs which already have current limiting resistors connected internally and are a direct replacement for the bulbs. This makes installation a breeze. They also give a very good sideways light but I also found that the spread of light was actually improved by removing the diffuser - strange but true
Oh and no need to cut the legs of the LCD - just bend the whole LCD back but spread the load on the legs (I used two strips of metal pressed together) That way you don't damage anything and it saves a lot of time and stress.
A note of thanks to all the above contributors for taking the time and trouble to provide so much valuable information. I'm not even doing mine, but found the read fascinating. I'm continually amazed at how co-operative and friendly this forum is. Love it!
'94 jzz30 gttl, 2 mini's one supercharged
Yes it is good. The t5 bulbs i used did have the resistor already soldered into the bottom. And as Mike says it made it so much easier. I only cut mine as i had to replace screen but i would try the bending method first though. One thing i also noticed is two of my original lcd backlight bulbs werent soldered properly onto the pcb board and i didnt even have to unsolder them.
QUESTION: Just installed a new LCD courtesy Rob Rojo's group buy. I also replaced all bulbs with ccfl tubes from E-Bay. So far so good, but the ccfl's are SO bright the interior of my car glows like a nuclear power plant.
I was thinking of installing a rheostat on the positive leg between the power feed (from the lighter) and the inverter.
Will this allow me to dim the ccfl?
If so, I have a spare Soarer dimmer (the one on the dash) - could I use this?
I think that CCFL tubes have a 'threshold' and if you reduce the voltage they might start to flicker. You might be better off fitting some kind of condom to the tube or painting it with coloured laquer to reduce the light output.
I find that even my LEDs are a little too bright at night so the CCFL must be quite overpowering!
Sc300 Non Turbo
Sorry to revive an old thread.
Has anyone ever changed the Green and Orange LED's that let you know if your AC is on etc...?
Or is it too difficult to cut them, remove solder etc... and resolder without damaging the unit?
JZZ30 Pov Manual LSD & black!
They are easy Matt, just de-solder the ones that are there are pop in the new ones. I did the transmission ones on my old V8 too..
SC400 GT-L V8
Yeah its easy matt, just don't lose the black plastic holder/seperater otherwise each led will shine through all the little led holes
redid mine in a green that matched everything else
BMW E36 Coupe 1UZFE V8 340i
Your going to hate driving at night Andrew, green is the most distracting colour for nightvision.
I originally did green in my UZZ30 6 years ago.
Drove me insane at night so I then went to a nice red.
SC400 GT-L V8
haha i will admit its pretty damn bright but..
its all matched together
you'd probably hate driving mine haha!
SC-400 V8 Stock
Green Lantern! LOL