[alanmay0]

Just wondering if anyone has found a solution to the dim light bulbs used to light up the instruments in the dash of the older cars. I have a 67 GTO and at night I can not see the controls for the heat/ac even though all the light bulbs are working and plugged into the correct sockets. Seems like there should be brighter bulbs that would fit these older cars and brighten up the dash. Any suggestions? If you have found something please include the part number and where you can buy them.
thanks
alan

[JLMounce]

Most of the dash lights including lights for the HVAC controls are 194 series lights. There are many companies making 194 LED's these days in a multitude of different colors. They can be had from places like the automotive chains, walmart, amazon etc.

Some are cheap, others are expensive.

From my understanding the only thing that you have to be careful of is how they are oriented during installation. Unlike the original filament style 194 bulbs that can be placed in their socket in any direction, the LED bulbs have a true + - flow path and the bulbs do need to be situated properly within the printed circuit electrical chain.

Because the LED lights don't require as much power, you get brighter, longer lasting lighting that is stock appearing, or customize the color of your choice.

[Schurkey]

They weren't dim when the car was new.

Clean all the dust from the lenses and whatever passes for reflectors. Verify that you have proper voltage to the instrument cluster lights. No corrosion in the connections, no voltage drop through the ignition and headlight switches except for the intended resistance of the headlight switch rheostat. There's ~20 feet of wire and who knows how many splices and metal-to-metal contacts that feed the dash lights, and it's probably all as ancient as the rest of the vehicle. For that matter, verify that the alternator is putting out appropriate voltage, and the battery is in good condition, with clean, tight connections.

It's really common for the lighting to be insufficient, but it's not the bulbs per se, it's where they're installed--behind discolored lenses, in front of dirty reflectors, and plugged into lower voltage than they were intended for. Of course, NEW bulbs that aren't silvered on the inside of the glass from age help, too.

[lust4speed]

One of the most outstanding memories I have is the view of the GTO instrument cluster pulling out of the dealership the night I drove my car off the dealer's lot in March of '67. Even with bright city lights the dash was vivid.

Fast forward to early 2019 and I'm driving home from a local show and I'm really having a hard time reading the speedometer. There is only a faint fuzzy brownish glow from the once proud dash. It finally hit me that something had to be done.

That was the moment I knew the dash had to be fixed, and the next weekend we yanked out the complete cluster and got down to business. First off all the bulbs we pulled out were originals and all had a black tint inside the glass. Next we disassembled everything and the plastic lens was hazy and covered in a lot of dirt. Dishwashing soap got it 90% better and the last 10% was hand applied polishing compound. Finished product looked like a new lens.

We could have probably stopped there but with the cluster sitting on the workbench it was just too easy to start ordering out bulbs from Amazon. It didn't take long to realize that most all the advertisements for LED bulbs are outright lies. We ended up trying two bright white LED bulbs and two blue LED bulbs. Three out of the four were actually dimmer that a new control Sylvania iridescent bulb from the auto parts store. The blues were disappointing and the hope of increasing the blue tint only made the the gauges dimmer with no additional blue observed. The LED that worked the best was a flat lens with three separate LED's per bulb. I'll have to do some digging to find what I bought.

I also cleaned the dimmer portion of the light switch and while it nicely controlled the incandescent bulb, the dimming of the LED's was almost unnoticeable and maybe from 100% down to 95% - basically no dimming. I purchased a $40 LED dimmer switch and it actually does control brightness from 100% down to zero, but after living with the LED's on full bright I could have passed on the dimmer. I'd probably skip the dimmer unless you drive on rural back roads a lot.

The phone camera washed the photo out a bit, but the gauges are a nice comfortable blue with no hot spots when looking at the panel.

[dataway]

So did you end up using the LEDs or the incandescent?

[alanmay0]

So good for you So what bulbs did you end up going with??? If LED do you have the part number please?
thank you
alan

[lust4speed]

Went back through the Amazon orders and came up with the links to both bulbs and the dimmer switch. I'll add that the bulbs that didn't do that well on brightness were also made by Partsam so just going by manufacturer isn't foolproof. Lights come in a pack of 10 and I used 9 since I didn't replace the turn signal, high beam, and alternator warning light bulbs.

Here's the lights that I like: Partsam lamp kit 1815

Here's the dimmer switch I used: Leisure Lectronics Dimmer

The dome light bulbs including the roof light and footwell lights were more of a pain and I don't really have a good recommendation. The 6000k bulbs are daylight which has a slight blue tint. The more expensive Ames dome light lens cover for the roof light has the correct light yellow tint and the LED being more towards the blue spectrum ended up a terrible green. I ordered out the cheaper Ames cover that is milky white and the light produced is a nice white now.

[shaker455]

Alan,
My 67' GP had nothing lit up.
I simply replaced all the old 194's with new and the dash now looks like new!
Jeff

[dataway]

Gonna order me a batch of those and do some experiments. Thanks for the info.

I'm betting that an inline resister attached to the output of the stock dimmer would put it in the proper range for LED bulbs. The Stock dimmer at the lowest setting would still provide way more power than the LEDs would need, a resistor would lower the output to a suitable range ... but would require some experiments to determine what value resistor would provide the correct range.

In my shop I've built a couple of "resistor boxes" with super heavy duty rheostats. One box does 0-500 ohms, one box does 0-50 ohms ... I can place them in a circuit and adjust them to find the right value ... then remove them, measure their resistance and just buy a single high wattage resistor to put into the circuit.

So basically before I install my dash I'll put in the LED bulbs, hook up 12v to the instrument panel, jumper in one of the resister boxes ... then adjust it till the stock dimmer works properly, then replace the resistor box with the proper single value resistor.

[lust4speed]

I'm betting the resistor won't work. LED's have a wide operating range and usually either light up or not, and thinking that the bulb will remain at a pretty constant brightness until the voltage drops below the operating threshold and the bulbs won't light up. The LED dimmer switch uses pulse width modulation (PWM) to send intermittent pulses of full voltage to the LED with the result the LED is only on a percentage of time which is perceived as less brightness.

I had quite a few photos of our testing the different bulbs but can't locate them. Initial testing was done with an old dash wiring harness where we could plug in different bulbs sort of like a string of Christmas lights. The next thing was to use one set of bulbs on the speedometer, another on the temp pod, etc...

Let us know what you find out. So many different bulbs out that there could easily be a better solution that we didn't try.

[alanmay0]

I have ordered the 1815 bulbs. Will see what they do.
thanks
alan

[69 Limelight]

Don't think the 1815's will help (2.8 Watts for 1815 versus 3.78 watts for 194). Get you some 168's (4.9 watts). That's what I did 10 years, 35,000 miles ago. Like someone above said best solution is take everything apart clean, polish, repaint. Clean connections and replace rheostat. I didn't have time for all that so 168's and new light switch. Has worked for me.

[dataway]

Lust ... you are probably right. It would probably be difficult to control voltage precisely enough to dim them in that very narrow range between lit up, and not lit up. Wonder if adding an incandescent bulb in series in the circuit would help.

I'll probably have the instrument panel in the "Laboratory" for a while

Anyone ever have problems with the brighter incandescents causing problems with heat? Melting lenses etc?

[OG68]

Here is a thread regarding 168 bulbs:

https://www.chevelles.com/forums/27-...ash-bulbs.html

I also read that the 168 service life is somewhat shorter than the 194

[steve25]

You may be literally playing with Fire if you replace a 3.78 watt 194 bulb with a 4.9 watt bulb as I do that think that those twist in sockets that hold those bulbs are rated for that much wattage no less the wiring and Headlight switch that feeds then!

Even just 4 or more of those bulbs run off the dimmer switch needs to handle 4.48 more watts then 4 of the 194 bulbs!
Even just 4.48 watts is another .37 amps at 12 volts that the wiring and dimmer on the Headlight switch needs to handle .

Don't be surprised if one day your dash board lights dont work and you have smoke curling up from under your dash!

[alanmay0]

Do the 168 bulbs fit in the sockets in a 1967 GTO??

[steve25]

Don't know, I was just reacting to what was posted about the bulb swapping.

[RocktimusPryme]

I put blue LEDs in mine. Made a difference. You could also just buy bright white LEDs if you want it way brighter.

[dataway]

Got the 1815 LED bulbs yesterday and played with them some. Seem like quality pieces, certainly bright enough that's for sure. Piercing bluish white light.

Hooked one up to a 12v power supply and using a 5K ohm potentiometer (as a rheostat) was able to dim it about 80%. The vast majority of the dimming took place in the first 1/3 turn of the rheostat.

Without all the blah blah math ... Lust is correct, I doubt they could be effectively dimmed with just the addition of a fixed resistor to the OEM dimmer. The OEM dimmer is probably only 50 ohm ... so just not enough range to dim them noticeably from whatever point a fixed resistor would start them.

I'll test the whole shebang when the time comes, but at present it looks like Lust's solution would be the best .... just hide the aftermarket dimmer under the dash somewhere.

[JSchmitz]

Originally Posted by lust4speed

One of the most outstanding memories I have is the view of the GTO instrument cluster pulling out of the dealership the night I drove my car off the dealer's lot in March of '67. Even with bright city lights the dash was vivid.

Fast forward to early 2019 and I'm driving home from a local show and I'm really having a hard time reading the speedometer. There is only a faint fuzzy brownish glow from the once proud dash. It finally hit me that something had to be done.

That was the moment I knew the dash had to be fixed, and the next weekend we yanked out the complete cluster and got down to business. First off all the bulbs we pulled out were originals and all had a black tint inside the glass. Next we disassembled everything and the plastic lens was hazy and covered in a lot of dirt. Dishwashing soap got it 90% better and the last 10% was hand applied polishing compound. Finished product looked like a new lens.

We could have probably stopped there but with the cluster sitting on the workbench it was just too easy to start ordering out bulbs from Amazon. It didn't take long to realize that most all the advertisements for LED bulbs are outright lies. We ended up trying two bright white LED bulbs and two blue LED bulbs. Three out of the four were actually dimmer that a new control Sylvania iridescent bulb from the auto parts store. The blues were disappointing and the hope of increasing the blue tint only made the the gauges dimmer with no additional blue observed. The LED that worked the best was a flat lens with three separate LED's per bulb. I'll have to do some digging to find what I bought.

I also cleaned the dimmer portion of the light switch and while it nicely controlled the incandescent bulb, the dimming of the LED's was almost unnoticeable and maybe from 100% down to 95% - basically no dimming. I purchased a $40 LED dimmer switch and it actually does control brightness from 100% down to zero, but after living with the LED's on full bright I could have passed on the dimmer. I'd probably skip the dimmer unless you drive on rural back roads a lot.

The phone camera washed the photo out a bit, but the gauges are a nice comfortable blue with no hot spots when looking at the panel.

I did the same with my dash. Amazing how much better it looks after cleaning and polishing. Did you paint your needles? I bought some paint. Tried it on an old spare gauge needle. It's not quite bright enough. Gonna buy another brand and test it out.