12v 23 watt LED replacement?

zackattack784 said:

So I got these LED turn signal bulbs.
BA9s LED Bulb - 9 LED Tower | BA9s and BA7s LED Bulbs | LED Car Bulbs | Super Bright LEDs

They look great and are as bright, if not brighter, than the stock bulbs. However, they give a turn signal out message on my dash . The turn signal indicator illuminates at half brightness and the bulb is dimly lit at all times with them in. The turn signals still function though.

It looks kind of weird having the bulb lit all the time and it's annoying as heck having my turn signal indicators on all the time. What's the cause? Not enough resistance? I'm using the electronic flasher relay that's stickied in this forum and currently have LED front pod lights, LED front turn signals, the Motodyamic integrated tail light, and 23 watt rear signals (that I'm trying to convert to LED) all running as turn signals.

Click to expand...

chunkygoat said:

That's some good thinking regarding applying the use of diodes, Motogiro.

I work on the LED Driver/Ballast team at Lutron and I feel I might be able to give some insight if the diodes do not help. I can't help but ask myself what are the specs of the 12v LED signal clusters you are replacing with the incandescent indicators?

The website does not provide any technical information regarding your signals. But, generally speaking -- you can't just replace the incandescent with an LED load -- you would need to interface an LED driver to provide the amount of resistance and current rating to MATCH your load.

If you do simple ohms law of the 12v 23watt rating of your indicators, you come out with these numbers:

6.26 Ohms
1.91 Amps
12v
23 Watts



I can't help but ask what is inside this electronic flasher relay you speak of. I am picturing a 555 timer and a relay that will pass the voltage/current to your load in certain intervals -- when power is applied to the timer through your indicator switch. If there is any current limiting circuitry inside this "flasher relay" then this most likely would be considered your driver.

You need a driver capable of supporting a 23w load. If you under drive your load, I can see more voltage available in the path of the dash board indicator -- hence it always being illuminated. I am wondering if you can find yourself a 12v 23w LED driver, used with your "flasher relay". Drivers usually aren't that expensive either.

Those are my thoughts.

Click to expand...

Motogiro said:

Thank you for the input! Lutron makes some trick controllers.

I think in this case there are no drivers except the flasher relay. I think I would use a driver if I want to be frequency specific to conserve power where I would use duty cycle. This is strictly a DC application. To drive the diode we only need to drop the current with a series resistor which you will find in all LED lights made for 12vdc applications.

It could be the flasher relay is not going to full zero volts which as you point out would be the driver in this circuit.

Remove the flasher and see if the dash lights go out? If they do it could be the flasher and I have an idea how to cure that. You may have a defective flasher relay

Disconnect the directional signal wires that are going to the Motodynamic tail light, try the flashers and see if the anomaly disappears on your instrument cluster. If so try the inline diodes.

Again, confirm all wiring is correct!

Click to expand...

chunkygoat said:

Thanks giro, Lutron definitely makes some high quality products.

I'm looking into these flasher relays and they appear to be just straight relays, I'm unsure why they specifically call them flasher relays -- or why they narrow the description down to the use of flashing an LED or incandescent load.

It appears to be just a standard relay that will take the logic level from your onboard CPU and apply it to the coil of the relay -- in turn actuating the switch of the relay to pass the 12v source to your to your LED loads. This makes perfect sense now.

I would double check to make sure your relay is appropriately rated, operating nominally (you should be able to hear the switch actuate every time the LED's illuminate (sounds like a CLICK), and that it is in fact wired correctly with the coil being the input from your CPU and the switch being the path of current flow from the source to your LED's.

I would double check the wiring, and make sure you hear that CLICK every time or else this to me suggests either the relay is improperly wired, defective, or not appropriately rated.

You can take some measurements if you have a multimeter measuring the voltage applied to the coil, the voltage applied to the LED's, and even the resistance from the source to your load (please make sure you disconnect power before taking resistance measurements).

If you're indicators on the dash are always on, it sounds like there is a potential there when there should not be. If you had the relay incorrectly wired, and the LED's are wired in parallel with the dash indicators, the paralleled LED load could actually be providing a path for current to flow back to the dash. I would first make sure your relay is wired properly, 2nd I would absolutely try the diodes. I am confident this would work -- but I suggest entertaining the idea of investigating this relay before coming up with a quick fix for something that might not necessarily be done correctly. Also make sure you are not using the NORMALLY CLOSED contacts of the relay! Double checking the relays operation and wiring eliminates this concern!

It may take some hunting, but these are the steps I'd take to narrow this down.

Click to expand...