Adding load resistors to LED tail lights
08-08-2010, 02:02 PM
#1
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Vehicle: 2012 mitsubishi eclipse spyder gs, 2001 hyundai tiburon
Adding load resistors to LED tail lights
With help from DTN, I got the load resistors hooked up. The process is incredibly easy.
First after installing the LED lights, (From where you may have gotten them, it doesn't matter.) obtain a 50 Ohm resistor.
You can get these for dirt cheap off of ebay.
Wire it in to the ground and constant live (running light) wire, which on the '01 tiburon is the solid green.
Find a place to mount the resistor as it gets quite hot. I ended up using a small tin thing that we use to hold window well pipe onto walls. It's rigid enough to hold the resistors off of anything but pliable enough to bend to where i need it.
I ended up using 2 sets of load resistors on the rear, one for signals, and one for the brake/cruise.
Signals end up being the same. Ground and solid colored wire.
First after installing the LED lights, (From where you may have gotten them, it doesn't matter.) obtain a 50 Ohm resistor.
You can get these for dirt cheap off of ebay.
Wire it in to the ground and constant live (running light) wire, which on the '01 tiburon is the solid green.
Find a place to mount the resistor as it gets quite hot. I ended up using a small tin thing that we use to hold window well pipe onto walls. It's rigid enough to hold the resistors off of anything but pliable enough to bend to where i need it.
I ended up using 2 sets of load resistors on the rear, one for signals, and one for the brake/cruise.
Signals end up being the same. Ground and solid colored wire.
08-08-2010, 02:31 PM
#2
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Basically what happens is the car looks for 12V on the negative side of the cruise control. The 12V on the brake is not grounded normally. The computer tests for 12V near the brake pedal. When you step on the brake, it applies ground at the brake pedal the sensing voltage disappears from the computer's sight. The computer then sees that you've depressed the brake pedal because it does not see 12V there anymore so it turns off the cruise control.
When you replace the standard resistive filiment bulbs with LEDs, you have a forward bias to deal with. The forward bias removes between 2-9V from the expected 12V. This is part of what makes a LED so energy efficient in the first place. It replaces analog component laws with digital laws (diodes, LEDs, transistors, all digital components).
so basically, it comes down to this...
<div class='codetop'>CODE</div><div class='codemain'>12V--+---LED----+---+-brake pedal----ground
+-resistor-+ +-----computer</div>
When using resistive components to simulate analog components for an upgraded silicone system it's best to use a hgh value resistor. A resistor of 5Kohm-1Mohm will do the trick of bypassing the forward bias from the LEDs and small enough of an electronic passageway that the LED still appears to be at full brightness. The smaller the value of the resistor, the more power it turns into heat and lets through and less power is available for the rest of the circuit.
When you replace the standard resistive filiment bulbs with LEDs, you have a forward bias to deal with. The forward bias removes between 2-9V from the expected 12V. This is part of what makes a LED so energy efficient in the first place. It replaces analog component laws with digital laws (diodes, LEDs, transistors, all digital components).
so basically, it comes down to this...
<div class='codetop'>CODE</div><div class='codemain'>12V--+---LED----+---+-brake pedal----ground
+-resistor-+ +-----computer</div>
When using resistive components to simulate analog components for an upgraded silicone system it's best to use a hgh value resistor. A resistor of 5Kohm-1Mohm will do the trick of bypassing the forward bias from the LEDs and small enough of an electronic passageway that the LED still appears to be at full brightness. The smaller the value of the resistor, the more power it turns into heat and lets through and less power is available for the rest of the circuit.