An Anti-flicker for Xenon HID Light, also known as error code eliminators, is a term that has been coined in the HID light industry in order to counteract the frequency/resistance differences between vehicle computers and HID light kits.
Anti-flicker kits are also described as:
These HID Error Code & Anti Flicker Capacitors are used in case your experiencing issues with your aftermarket HID Kit. The two most common issues these capacitors are made to fix are light flickering (stobe effect) and “bulb out” indicator lights.
Anti Flicker Issue: The flickering problem is most common when installing HID lights in a car that has dual functioning low beam bulbs with active Day Time Running Lights, also known as DRL’s.
Low beam lights w/ DRL function work like this. When your lights are in the off position a pulsed voltage flows to your factory halogen bulb giving off a dimmer light. When you install HID’s in the place of your halogen bulb it just causes the HID capsule to flicker. The Anti Flicker Capacitors will even out the factory DRL current and stop the flickering.
Bulb Out Issue: Many newer cars have an indicator light to warn the driver if one of the headlights has burnt out. Now since HID kits run on a lower wattage then normal Halogen headlights your car will think the headlights have burnt out. This will in return turn on a “Bulb Out” indicator light, This usually does not affect the lights function but is annoying. These capacitors take place of the wattage loss and fool the car into thinking the halogen bulbs are still installed. After install the “bulb out” indicator light will then turn off.