LED Headlights: Do You Need a Decoder Harness? Common Issues & Solutions

When installing LED headlights in your vehicle, you may encounter issues that indicate the need for a decoder harness. This guide will help you determine if a decoder harness is necessary and explain common problems and solutions associated with LED headlight installations.

Common Issues Requiring a Decoder Harness

When you install LED headlights, you might experience the following problems, which suggest that a decoder harness is needed:

  1. Bulb Flashing When Turned On
  2. Headlight Out Error Displayed on the Dashboard
  3. Bulbs Stay Illuminated After Turning Off
  4. Abnormally Dim Light Output

No more errors or flickering. The newly designed decoder harness addresses all these issues! It is designed to handle both CANbus and PWM systems used in the latest vehicles, providing a plug-and-play solution for any LED headlight and fog light conversion. This harness has been tested for compatibility with most Dodge, Chrysler, Jeep, VW, BMW, Audi, Mercedes-Benz, and many other CANbus systems currently in use.

Understanding CANbus and PWM Systems

Power Monitoring

Some CANbus systems monitor the current input of the light bulb they control. When they detect a current larger or smaller than the original bulb’s specification, it causes a problem. The decoder harness can help by accommodating the power demands of the new LED bulb, allowing the system to adjust to the aftermarket product.

Pulse Width Modulation (PWM)

Pulse width modulation (PWM) technology is used to reduce the heat output of halogen bulbs, extend their lifespan, and save power. However, LED headlights require a constant current, not the pulsed power supplied by PWM systems. Installing LED headlights in a vehicle with PWM configurations can result in flashing bulbs or bulbs that turn off after a few minutes. The decoder harness includes large capacitors that store power to eliminate the pulse, providing the LED headlights with a constant flow of current.


Keywords: LED headlights, Decoder harness, LED headlight installation,Bulb flashing, Headlight error, CANbus systems, PWM systems, LED headlight problems