My 69 every bulb is led except headlights.
I needed 2 electronic flashers from autowire. Everything blinks as normal.

For headlights I made a relay harness setup I have T3 bulbs and they run bright

 

The tails are even better but I don't have a video of those.

 

Just did my 55 Bel Air.

That special flasher is a must.

 

I've replaced every single bulb on my '71 with led's….interior (dash, dome light, glove box light, light at the rear of the console as well as both footwell lights) and exterior (headlamps, front side markers & parking lights, taillights and backup lights and under hood light). The only ones I did not replace (only because I forgot... ) are the rear fender side markers and the license plate light. My friend who did the job foe me also installed some resistors to prevent hyperflashing.

Claude.

 

My friend who did the job for me also installed some resistors to prevent hyperflashing.

Honestly, that was kind of a dumb move by your friend. In a newer car that has no actual flasher module but has things controlled by a computer, resistors need to be used to show the computer the same load on the circuit to keep things functioning properly. However, on these old cars that use an electromechanical flasher module, all that is needed to prevent hyperflashing is to use an electronic flasher module. An electronic flasher module is cheap and easy to install and requires no modifications to the electrical system. Unless required to "fool the system", resistors kind of defeat one of the advantages of using LEDs in the first place which is to lower the load on the wiring.

 

Claude please send your Friend here to me

As at some point I want to do a AAW Classic Update Kit Rewire to my 67 plus all Bulbs in the Dash/signals etc.

I already have the Headlight Relay Conversion Harness from Painless to have/increase direct Power from the Battery/Alt

 

Just to help everyone out, the hyper flash cause:

The flasher is a bi-metal spring. When you first turn on a signal, current goes through the spring, the bi-metal (2 different metals) spring heats up and since it's 2 different metals one side will expand more than the other and it bows, disconnecting the circuit. This turns your turn signal bulb off just like turning the switch off. The spring cools and goes back to resting position which reconnects the circuit and turns the bulb back on, and the cycle repeats until you turn the flasher off.

LEDs consume WAY less current than bulbs, so there's less current, which means less heat, which in turn makes the spring bow less, so the turn signal flash is quicker. Just like when a bulb burns out, you get quicker flashes. An "electronic" flasher uses a timer circuit instead of a bi-metal switch so the amount of current flowing through it has no affect on the flasher's consistency.

Greg if you were closer I'd be elbow deep tossing wires and getting everything right for you.

 

Just to help everyone out, the hyper flash cause:

LEDs consume WAY less current than bulbs, so there's less current, which means less heat, which in turn makes the spring bow less, so the turn signal flash is quicker. Just like when a bulb burns out, you get quicker flashes. An "electronic" flasher uses a timer circuit instead of a bi-metal switch so the amount of current flowing through it has no affect on the flasher's consistency.

Not quite

A traditional bi-metallic flasher with LESS load won't cycle at all, or very slowly. It is all or nothing. Not enough current will produce not enough heat for mechanical action.

Modern vehicles with electronic flashers with built-in bulb outage detection flash rapidly when less then stock load is detected on the signals to warn the driver.

Conversely, overloadingg an old fashion bi-metallic flasher will result in too quickly of flashing. That is why heavy duty "cans" were introduced.

One other reason LEDs use resistors is in semi-modern cars that used normal filament bulbs, but could detect failures due to lower resistance/current, plain LEDs would not be enough to let the car know a working bulb was present, so they added resistors to increase the resistance. Now the car "senses" the bulb, but can't tell if it works.

Actually the LED tails on many modern cars pulse, the duty cycle provides less strain on the LEDs (heat build up) while providing the maximum current peaks to get the most light output. Manufacturer data sheets will show peak current allowed for what duty cycle when it comes to LEDs. The cars electronics can then detect a "bulb outage" based on changes on the drive current seen. Watch a video sometime of a Beamer at night when the refresh rate of the camera doesn't match the modulation rate of the rear LED lighting. You are correct as well with traditional resistors strapped across the power input to represent "correct load" to satisfy CAN Bus requirements of the electronics.

In the most general sense, LEDs do require some sort of current limiting to prevent damage.

This is because LEDs are current driven devices, meaning you have to reduce the current, not the voltage, for them to dim. The rheostat dimmer on your headlamp switch reduces voltage. The best way IMHO to dim LEDs is by using PWM.

They are current based devices. However, by varying the voltage, you can effectively "dim" the LEDs.

This has been discussed many times before on this site where people complain the dimmer on the factory switch does NOTHING now that they have installed LEDs. The dimmer on these cars is a rheostat of only a few ohms. It will not develop the same voltage drop across it with only a mere fraction of the current drawn by the LEDs! You can "cheat" by installing a load resistor on the LPS connection spade on the fuse block. By drawing enough current, there will be enough voltage drop from the dimmer control to "dim" the LEDs along with the varying voltage across your dummy load resistor.

Pulse Width Modulation is the ONLY correct way to vary brightness of LEDs for maximum longevity.

PWM has been around a LONG TIME.

To interface a PWM control to your old school dimmer rheostat would take some creative circuitry. Something like an Atmel Atmega microprocessor coded to detect a range of voltage from the rheostat with a small dummy load and then provide an PWM output to something that could handle the current like an appropriate sized MOSFET, or use your microprocessor interface to translate to the input of a traditional PMW control chip. Control units like this one, would require rewiring the LEDs in series.

https://www.mouser.com/datasheet/2/315/AN30888A_E-1141882.pdf

 

Will the dash bulbs dim the same as incandescent?

 

They will if you buy the correct dimmable LEDs. Not all LEDs are dimmable.

 

One other reason LEDs use resistors is in semi-modern cars that used normal filament bulbs, but could detect failures due to lower resistance/current, plain LEDs would not be enough to let the car know a working bulb was present, so they added resistors to increase the resistance. Now the car "senses" the bulb, but can't tell if it works.

 

The availability of dimmable automotive LEDs is limited in quality and colors. When I did LEDs for the instruments in my 69 pickup, I just went with regular LEDs and gave up the dimmable capability altogether. Don't really miss it as the dash lights were always too dim anyway with regular bulbs, even at the highest setting.

 

I changed every light out. Made a big difference. All of the led fit in the original socket. Anyone who drove in the 60's and 70's remember that every car had a burn mark in the lens covering the roof courtesy light. Led solves this. I went through changing out the headlight with halogen, and every other option, trying to get the lights brighter. My last try did the trick and I fully endorse the 575 LED kit from Dapper Lighting. They are projector lenses and fit my headlight housing with very little to no modification. They are a little pricey, but take it from someone who has tried every option, you will be able to see better. The customer service is great. I put the led lights on the parking lights, backup and taillights as well. All good

 

Maybe I am getting a little ahead of myself but after.viewing a you tube video from a manufacturer of pwm for automotive applications it appears as though the dimming would not be done with the factory dimmer switch but with a little screw on the pwm so that is not very convenient.

 

Joe,
Is there any drawbacks to adding a resistor the the lps terminal?

 

I am hoping someone will submit a detailed tutorial on LED bulbs for our older cars.

 

Bill, there's no real need for a tutorial… Just replace all the bulbs with led's and chose between putting resistors to prevent turn signal hyperflashing (which I did) or go with an electronic heavy-duty flasher and bingo!.. you're done. :yes:

Claude.

 

There is a 3rd choice. Just put regular incandescents in the turn indicators and won't have to do anything. The turn indicators are something I woundnt care if they remained a little dimmer as they can be seen if on or not with regular bulbs. Also as I already mentioned a few people that went with led's and don't have dimming ability say that the high beam indicator is annoying with an led. This is another bulb that an incandescent does fine. The problem is all the other guages. They need led bulbs.

 

I don't have any LEDs in the dash of the wagon. When I went with LED tails but still had regular incandescents in the front flashing was fine, but when I put LEDs in the front as well, I had incorrect flashing and had to install an electronic flasher module. Didn't matter what bulbs I had in the indicators in the gauge cluster, the tiny incandescents in the indicators don't provide enough resistance to make things work right without an electronic flasher.

 

All the parts stores around me carry electronic flashers. I know most the counter people don't know much anymore, but there's enough people switching to led lights that they should know exactly what you're wanting if you ask.

Or go down the light/flasher aisle. Look for electronic flasher w/ the 2 blades at 90 degrees and you're done!

Good luck!