Tutorial: Secondary LED indicator in Instrument Cluster

[bkwanab]

Here's another attempt to attach the pictures of the CCI.

Phil Grice
Carlsbad, CA

[bkwanab]

Well it worked this time.  I wonder if I had too much text to accompany this many images.  Ignore the middle image.  That was an error I made while downsizing.

The first image clearly shows the mask positions and that it is clear, I.e. uncolored.  The second shows the level of brilliance from the RS LED that I used.

Now if I can just find a suitable green, or even better blue, LED I will be even happier.

Thank you everyone at Area 451.  I understand why this location was not built into the standard package.  Perhaps you may want to kit it as an option.

Here are a few more  images showing the hole I made (drilled four small holes and opened up with a surgical scalpel), the size and the additional hole I used to route the two new wires.

Phil.
Carlsbad, CA

[admin]

Sorry for the trouble you're experiencing.  Another option is you can upload them to a service such as PhotoBucket.com and then link to it here?  The "BB Code" for doing that is explained here.

When this site was set up, remember we were full on in the middle of making cruise controls.  And nobody here pretends to be a web designer.  We just went out and found a forum package to get something up and it seemed to work.  I can't really say I know the differences between the browsers and what will or won't work in one or the other.

[intocoasters]

Just finished the mod ..... LUV IT!

I used the 5mm LED (2.4v 20mA) and shaved the sides of the LED on my grinder just enough to get it to wedge itself in the channel.

My cruise logo is also the second tunnel down from the top left.  I also drilled a new hole for the wire exit in the back of the speedo housing.

You know, the cruise already looked stock.  But now it'll be difficult to convince people that its not a factory option.

[admin]

Thank you for the photos bkwanab!

Both the cars I have ready access to have the ECO symbol, both in the top right as well as the position you used (yes... 2x "ECO").  I sure wish they had the cruise symbol like it seems most people have    I guess that's what we get for taking our cars pre-release.

I'm going to edit the tutorial to emphasize that the 2nd channel is the preferred location if you have the cruise symbol.

intocoasters, you mean 2nd down from the top right... right?

[admin]

I don't like the idea of routing the waire through the opening used in the published procedure as they are used for the mounting clips and I was concerned about pinching and possibly shorting the wires.

That's interesting... another difference with our pre-release cars?  Or perhaps I lost the clips and never noticed?  Or I was careless and just didn't pay attention.  When I get a chance I'll go tear it apart again but I'm sure I would have noticed two clips.  If those holes are indeed for clips then I agree you should not run the wires there.

[intocoasters]

    yes, I meant right... I was thinking of it from behind the dash as that is how I was aligning the LED.

Also, my dash has the 2 clips that use those holes as well.... I am sure there is enough room for the wire to go around the clip.   It was just my preference.

[John_H]

From the instructions:

First you take off the decorative frame at the front. Be careful, but there's really no trick to it - you just carefully pry it loose. It is held on with several somewhat delicate clips.

I'd suggest there is a slight trick:  there's a small dimple that engages the decorative ring to the body on the very bottom center; press in on the body there and the ring is more free to be manipulated out of the delicate clips.  Minor point but it took me a few minutes to find it.


Since surface-mount LEDs are typically wider angle than most discrete LEDs (even if the ones used on the board are domed) I'd suggest a wider angle LED is fine (say, 30 degrees) and less prone to position problems.  The white plastic tube is used to help integrate the light into a more uniform field for the clear cruise-control aperture - efforts that are thwarted by narrow-angle LEDs.  To keep the integration working, keeping the LED toward the back is probably a good bet.

I'd like to make some measurements from the existing red LED to know what voltage and resistor is used to drive the diode.  If I can, I'd love to make a small run of thin boards with a single surface mount LED that gets slipped in behind the white plastic shroud flush against the pc board so no drilling would be required.  I should be able to use any color LED for the indicator by choosing what kind of charge pump to use.  Without the charge pump, using a color other than red would tend to keep the new LED from turning on without disconnecting the original red LED.

If anyone from Area451 would like to discuss rather than my trying to futz around clumsily with a multimeter and potentiometer, I'd love to hear through personal message or email.

I'm proud to be a customer!  I'll let people know if/when I get something together I can share.

- John_H

[admin]

Sounds like you know more about LEDs than I do  

Here is the exact LED that was used in our switch arm:  APT1608SRCPRV

That should give you the data you need. 

I really like your idea!  Something we hadn't thought of at all and it should provide a more finished result.

Thanks also for the tip on removing the frame.  It came off so easy for me I didn't really think about it too much.

[Horseman]

Okay... I just happened to be looking around again at Radio Shack's website and I happen to notice the LED located here. I don't know HOW I missed it the first time. It seems to match the upper limit of the specs you posted nearly to a T, though I have to wonder if this LED might be TOO bright. I ASSUME... you can always trim the brightness down with a resistor, correct? Lemme know your thoughts on this particular LED. Thanks.

Alex

[bkwanab]

John H/Admin:  I also found that by squeezing the bottom of the speedo trim it was quite easy to remove.  I didn't notice a bump but I wasn't looking ...  I have a tame LED engineer also looking into wiring in a discrete transistor so we can take any convenient 12 V source and thereby power a higher voltage blue or green LED, surface or thru hole.  (He's planning the do the math backwards to determine the actual voltage available that is illuminating my RS LED so nicely but if Admin would share that specific info it may save us some time figuring out for the optimum blue, green, LED voltage we'd need.  The current voltage range suggested is quite wide.)

Horseman:  I tried that LED and was disappointed as it was too dim in my opinion.  And I wanted a green LED badly.  Still do, but blue would be a nice alternative.

When I made up my wiring harness for the LED I made it about a foot too long so I could solder on a sample LED and see how it looked easily, cut it off if dissatisfied and then solder on the next one.  I tried five varieties before deciding the RS 276-309 was acceptable.  But its red, dammit!

I had to run up to Orange County today and it was nice to set the Cruise on 4000 rpm in 5th (I'm not going to admit how fast I was going here!) and watch all the wallowers trying to keep up or stay in front.  I passed a new Civic Coupe at least five times as he'd speed up and then then slow down again, repeatedly.  I haven't hit the limiter yet but I've been close I think.

BTW, I've found if the speed starts to drop when climbing steep grades, clicking down a cog will keep the motor on the boil and the cruise control maintains that speed as one would expect.  Perfectly.

Thanks again Area451.

Phil
Carlsbad, CA

[John_H]

Admin - The LED isn't near as important as the curcuit driving it.  There's typically a driver with 1) a drive voltage and 2) a series resistor, both of which directly affect how much current is available to some random LED.  Knowing how much current at what voltage helps to size for the right brightness.  Some drivers actually supply a given amount of current at whatever voltage the LED needs.

I'd like to use a charge pump for the blue to up the voltage to an acceptable level; green through red might get by without the extra push.  The surface-mount LEDs I'm looking at buying are pretty high effieciency devices so I'm less worried about being dim than I am being too bright but too-bright is easy to change.

- John

[Horseman]

Well, if anyone finds an appropriate green LED, surface mount or otherwise, that will get the brightness on a par with the other icons in the display, please post it! I'm hoping to pull my unit apart this weekend and get something going.

Thanks!

Alex

[Horseman]

John_H, I'd be interested in installing a charge pump if it will get me a bright enough green. I'm assuming this charge pump is not much more than a simple amplifier that I hook up between the LED and the circuit, and that I'd have to bring raw voltage to the pump. Is that accurate? Let me know!

Thanks.

Alex

[intocoasters]

John_H, I'd be interested in installing a charge pump if it will get me a bright enough green. I'm assuming this charge pump is not much more than a simple amplifier that I hook up between the LED and the circuit, and that I'd have to bring raw voltage to the pump. Is that accurate? Let me know!

Thanks.

Alex

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