CAN Bus LED Bulbs - FAQ

You may have seen CAN Bus bulbs on our website and were unsure of what that meant or if they were compatible in your vehicle. Not every vehicle is CAN Bus equipped, so refer to your vehicle’s manual to be sure. If your vehicle is CAN Bus equipped, read on to see what that means when selecting bulbs for your car.

LED CAN Bus bulbs are available in many different varieties and applications.

CAN Bus stands for Controller Area Network Bus. Prior to the creation of the CAN Bus system, vehicles housed various electronic control units, or ECUs, that controlled the wiring for different parts of the vehicle system. Engineers wanted to develop a way for these ECUs to communicate with one another in a bus communication system. Thus, the CAN Bus system was created to allow individual vehicle systems to report if they were functioning properly.

While originally starting in European vehicles, CAN Bus systems have become standard for newer American and Japanese-made cars built in the past 20 years. Vehicles with CAN Bus systems also have less wiring in their electronic control units.

CAN Bus LED bulbs are bulbs that are made specifically for CAN Bus-equipped vehicles. These bulbs have built-in resistors that simulate the load of the original halogen bulbs you want to replace. The built-in resistors create enough resistance on the circuit so that the CAN Bus system can register that the light bulb is working.

CAN Bus ready is a term used to describe a vehicle headlight, taillight, running light, or turn signal bulb that can be installed into a vehicle that uses a CAN Bus system for its lighting. You might see these vehicle bulbs also referred to as a “CAN Bus compatible bulb”.

While every vehicle’s CAN Bus system works differently, most “bulb-out” indications for areas such as headlight, tail, brake, and running lights can be solved by using a CAN Bus bulb.

Halogen bulbs original to your vehicle system consume more power than LED bulbs. Therefore if you replace halogen bulbs with LEDs, many vehicles will display a “bulb-out” warning light or not register that the lights are working correctly since the vehicle system expects to detect a higher current. For vehicles with a CAN Bus system, installing LED CAN Bus compatible bulbs can prevent the “bulb-out” warning signal since these bulbs have built-in resistors that simulate the expected working power of a halogen bulb. 

If you use a standard LED bulb without a load resistor in a car using a CAN Bus system, you might get a “bulb out” dashboard indication (if your vehicle gives notifications) since the power draw is too low for your vehicle system to register as a working light. In most instances, adding a load resistor to a standard LED car bulb install will fix these error messages.

The factory relay begins to hyper-flash when the load across the circuit drops below a certain threshold. In most cases, the use of a load resistor with a CAN Bus bulb can prevent hyper-flashing issues in turn signals for both CAN Bus-compatible and non-CAN Bus-compatible vehicles. However, keep in mind this is not a solution for all cars. 

If installing a CAN Bus bulb and load resistor does not solve your hyper-flashing, adding an LED flasher module might work. For more information, see our blog post How To Fix Hyperflashing Turn Signals

Yes, you can use CAN Bus LED bulbs in vehicles that do not have a CAN Bus system for lighting. CAN Bus bulbs simulate how regular car headlights, taillights, turn signals, and running lights operate, so they are equipped to work in vehicles with or without a CAN Bus system.

The easiest way to determine if your vehicle uses a Controller Area Network Bus is to remove a light and turn on the vehicle to see if it gives a warning. However, this will only work if your vehicle displays these types of warnings. For vehicles that do not show notifications, check your vehicle’s owner's manual.

Some situations will require a load resistor to be added to a CAN Bus bulb. If your turn signals are experiencing hyperflash, you may need a load resistor to indicate to the relay that your lights are working properly. If your vehicle does not have any hyperflashing issues, you most likely will not need a load resistor.

A CAN Bus decoder is another name for a load resistor. These products are designed to create enough resistance on the circuit for the CAN Bus system to recognize that the light bulb is working. Load resistors and decoders can help solve hyper-flashing issues as well as bulbs flickering.

To view our selection of LED CAN Bus Vehicle Bulbs, click here.

For technical questions, don’t hesitate to call us toll free at 866-590-3533. Our customer service and technical support teams are available from 8:30 a.m. to 6 p.m. CDT Monday-Thursday and 8:30 a.m. to 4 p.m. CDT on Friday.