Custom LEDs for Your Instrument Cluster
 

So I had my instrument cluster out (as you do) and never wanting to have to do that again, I replaced the #158 bulbs with some LEDs.

The old ones are Toshiba branded, here's the factory original bulb.
https://cimg9.ibsrv.net/gimg/www.rx7...bff61bb3da.jpg


You can buy the #158 LED replacement bulbs for cheap

https://www.amazon.com/Jtech-8-SMD-W.../dp/B00AQB8JFQ

But I was impatient so I made these from dimmable strip lights.

https://www.amazon.com/LEDwholesaler...dp/B002Q907EW/

The short version is just 3 LEDs and fits where a bulb would if the application is tight. For the deeper spots you can fit 6 LEDs from the strip.

The #158 filament bulbs used about 220 mA and get hot, not hot enough you can't hold them, but hot.

The LED replacements use about 10mA per LED and don't feel warm at all. And these dim perfectly with the control on the dashboard.

https://cimg4.ibsrv.net/gimg/www.rx7...a513629901.jpg

More details on how you built these up please. Did you solder the contacts on? Whats the
material insulating the two contacts you added? Moar pics of the process if you have em.

How did they look in the console? Pics? Pics of old console with lights on before removal?

Lots of questions but I'd never seen these before. And 16ft for ~$12 is a bargain.

They look and perform exactly as the bulbs did. I did not photograph but I did place LEDs on the right side and kept the #158 bulbs on the left side for a comparison. The dimming, brightness, and color were indistinguishable. These are 2700 K, pretty yellow.

You need to keep track of the polarity, so you might need to experiment with the orientation of the re-socketed assembly. I mark the + side of the LED with a red sharpie

The LED light strip is pretty tough, but extreme bends can break the circuit, so test repeatedly as you build it up.

I used Kapton tape to insulate, it's very heat stable, not that I worry about the heat from the bulb, but vinyl electrical tape in a hot car would not work long term. An okay substitute would be heat shrink tubing, I think.

https://www.amazon.com/Mil-Kapton-Ta.../dp/B006ZFQNT6

So I cut the LED strip to the length I need and use opposing solder pads:

https://cimg7.ibsrv.net/gimg/www.rx7...5fdd66309b.jpg

The plastic material is really heat resistant and the pad takes solder well. Make sure you use electronics solder with a flux core.

https://cimg8.ibsrv.net/gimg/www.rx7...7b535fb2a7.jpg

Tin your conductor and then attach to the beaded pad. I used multi-filament copper wire here, but it's much better to use a solid copper conductor as in other shots below.

https://cimg0.ibsrv.net/gimg/www.rx7...f188f95f5e.jpg


For the rigid base piece I cut a small length of plastic duct hanger strap that seemed like the right thickness, really any non conductive hunk of something from your recycling bin would work:

https://cimg8.ibsrv.net/gimg/www.rx7...baa444e498.jpg

Fold the strip, peel off the adhesive backer, then stick it to the base (Note that this shot doesn't have the conductor soldered on, it's just to show the concept).

https://cimg7.ibsrv.net/gimg/www.rx7...9aee52c11b.jpg

Squeeze the light strip to stick on the base, and wrap the Kapton insulator (or apply heat shrink). Imagine that the wire is really soldered to the light strip's copper pad at this point, just didn't have a good shot:

https://cimg1.ibsrv.net/gimg/www.rx7...6ef2217c11.jpg


Bend the conductors back up, make sure they are above the insulation layer and that the loop bottom matches the bottom of the base. This one is a little bit too high.

Also, if those conductors were soldered as in the real thing, I could have taped this demo much tighter/neater. You get the idea.

https://cimg4.ibsrv.net/gimg/www.rx7...ffd8ed9367.jpg

Test!

https://cimg1.ibsrv.net/gimg/www.rx7...de001fe539.jpg

This is awesome,im going to try it out

how many of the 158 bulb does the cluster take???

There are 9 of them. The large sized bases, like the blinkers, gauge illumination, and some rando things like rear defrost indicator, and headlight up/down signal.

Some are really deep channels, for others a bulb just fits and you have fold up the LED strip.

Nice work; well presented. Thanks for the time to demo this.
So. Presumes that, with all the @#$! LEDs made, there is NOT a plug-and-play LED for this type of bulb?? damn.

Stu Aull
80GS
Alaska

Oh there are plenty, link for some in the original post...I just had this stuff laying around so I made my own.

https://www.amazon.com/Jtech-8-SMD-W.../dp/B00AQB8JFQ

LOL! well, thats great !
thanks - I'll go the Lazy Route then...
:)
Stu Aull
80GS
Alaska

What's the illumiation on the dash like now? Got any pics? I never had much luck using different types of wedge type led bulbs - always get bright spots and dark spots no matter what i try - plus the bluish white colour on all available leds really clashes and looks weird when it gets filtered through the backlight.

The dash illumination matches the old incandescent. I used only 3 or 6 of the LEDs per socket, and only 1 or 2 face the console surface directly, the others are side facing. Maybe that's the difference between these and other styles, fewer LEDs and multi facing.

I'll take some shots tonight ans see if I can get a sense of hotspots and a good color balance.

Tom

Finally took a picture. White balance is set for incandescent. Manual exposure. Looking at this photo, it seems like the fuel gauge is dark compared to the rest of the cluster. In real life, I never noticed that.
Maybe my exposure is a bit too dark and under-represents the speedo. Whatever the case, there is clearly a gradient in the photo, that I don't notice by eye. Ha! Maybe I'll see that from now on and it will drive me crazy ;).

I don't have any "before" pics with tungsten bulbs to compare.

https://cimg7.ibsrv.net/gimg/www.rx7...14ebed1777.jpg


Here's a video of the dimming performance, they start very low and come up smoothly, no sudden "pop" on, just like filament bulbs.

https://drive.google.com/file/d/0B-l...ew?usp=sharing


.

Looks good. Better than anything i tried on my other cars. What do you mean by the white balance setting? Are you able to play with the colour somehow? Speaking of which - the backlight is usually orange on these, yeah?

Exactly, all the cluster illumination goes through orange plastic filters, and where you see orange in the painted areas, it really is orange.

The LEDs are 2700K which is pretty yellow and match tungsten filaments pretty well.

I note the camera's color balance is set to tungsten (this just means it interprets the light expecting it to be the color temperature of tungsten) so if you saw "off" colors you would know it would have been due to the new LED light source. In automatic mode, cameras use automatic ISO, shutter, aperture and white balance. In that mode, they try to accommodate the light source to make white look white rather than shifted. So when you see a "yellow" picture, it's because the white balance is off in the camera, maybe it thinks daylight but sees yellow tungsten.

Ok, so it still looks nice and orange then? Nice work! Also, that's a low mileage specimen you have there!

Thanks! I bought it from a really nice guy in OH, who was the 2nd owner. His friend had purchased it there and owned it for 20 years. The seller had it for 7 more and got it to 31K. I've had it for 6 years now, damn that went fast!

I keep it out of the winter mess here in New England so it cuts my driving season in half. But damn, sit inside it and it's 1983. I am a complete stereotype as I drive with the stereo blaring The Cure, sun roof open, the wind blowing where my hair used to be ;).