Understanding CANBUS HID kits, what they are, and how they work.
Last updated: September 15, 2023
Xenon HID conversion kits can vary greatly from one manufacturer to another with respect to wattage, color temperatures, and even the electrical systems such as ballasts.
In this guide, we’ll focus on, explain, and explore the two main categories of HID kits: CANbus and non-CANbus Xenon HID conversion kits.
We’ll start with a brief explanation of a CANbus system and its role in headlights. We’ll then go over the differences between a CANbus and normal HID kits, and conclude with recommendations and frequently asked questions.
If you’ve been driving for long enough, you’ve surely come across the dreadful check engine light or other common warnings such as an active parking break or low windshield washer fluid.
How do these notifications come about? You guessed it! Through the CANbus system. The CANbus is to a car what the nervous system is to the human body.
A CANbus is a computer system that centralizes, reads, interprets, displays, and prioritizes messages from multiple microcontrollers and devices (such as sensors) technically known as Electronic Control Units (ECU).
In the context of a car, for example, headlights, parking breaks, gas and windshield washer fluid levels, airbags, engines, brakes, etc. are individually monitored using ECU’s, which continuously communicate with the CANbus system.
Given the importance of automotive lights, many vehicles have microcontrollers and sensors in their headlights. The main purpose is to scan and monitor whether the lights are working or not.
When introducing foreign (aftermarket) bulbs that don’t have the exact specs, electrical output, etc. as standard halogen bulbs (such as LED or Xenon HIDs), the CANbus system can start acting up.
Your lights might not work at all or flicker with LED or HID bulbs installed but that issue can be easily resolved with a CANbus HID kit or a normal HID kit with an anti-flicker accessory.
The first and most important difference is that CANbus HID kits have CANbus-ready ballasts while regular HID kits have standard ballasts.
In an HID conversion kit, ballasts regulate the flow of power, which is exactly the aspect of headlight bulbs that a CANbus system scans to ensure proper functionality.
CANbus-ready HID kits have integrated capacitors, can be installed as-is and your headlights will work perfectly without any dashboard errors or light flickering.
The capacitor is what signals to the vehicle’s CANbus system that everything is good with the aftermarket bulbs.
The downfall of CANbus HID conversion kits is that they are more expensive, the ballasts are quite big, a lot less efficient (leading to a shorter lifespan), and will either cause problems or not work at all on vehicles without CANbus systems.
Regular HID kits, on the other hand, have standard ballasts, which are not “naturally” compatible with CANbus systems. However, these kits come with an extra component called the anti-flicker, capacitor, or warning-canceller. Essentially, the capacitor is external compared to CANbus-ready ballasts which have it internally.
The anti-flicker component replicates the exact effect of a CANbus-ready ballast but does so a lot more efficiently. As a result, regular HID kits are cheaper, the ballasts are significantly thinner and more efficient (leading to a longer lifespan), and will work with vehicles with and without CANbus systems.
|CANbus HID Kit||Regular HID Kit|
|Work on CANbus system?||Yes||Yes|
|Work on regular system||No||Yes|
If you’re in the market for a Xenon HID headlight conversion kit, we would recommend going with a regular, non-CANbus kit for several reasons, most of which are summarized in the table above.
Regular HID kits are CANbus-compatible with the external capacitor but come with the advantage of being less expensive, lighter and slimmer, more efficient, and with a longer lifespan. Further, if your vehicle is not equipped with a CANbus system, the lights will work perfectly, unlike a CANbus-ready HID kit.
“CAN” stands for Controller Area Network while “bus” refers to a communication network that links components inside a vehicle together.
As a general rule of thumb, the following vehicles have CANbus systems:
If your vehicle has a CANbus system, you will need a capacitor (warning-canceller/anti-flicker). A CANbus HID will have the capacitor integrated directly in the ballast and a normal HID will have the capacitor as an extra, external accessory.
A CANbus error or a Bulb Out Warning (BOW) can be eliminated using a capacitor (warning canceller/anti-flicker/CANbus adaptor) accessory.
A CANbus decoder is a capacitor. The capacitor signals to the vehicle’s CANbus system that the headlight bulbs are working properly, which allows them to function uninterrupted and error-free.
A CANbus ballast is a ballast with an integrated capacitor. The ballast’s job is to regular the flow of current.
The capacitor signals the CANbus that the bulbs installed are working properly and as a result, the Bulb Out Warning will not show, and the lights will not be prevented from turning on.
A non-CANbus ballast is one that does not have an integrated capacitor. However, external capacitors can be connected to the ballast which essentially makes it a CANbus ballast.
No. However, since 1996, all vehicles in North America are required to have an On-Board Diagnostics (OBD) connecter.
Disclaimer: The information contained on this page is provided free of charge to our visitors. It was prepared to the best of our abilities and with all the information available to us at the time of writing. We reserve the right to change, remove, or update any information contained on this page at any time and without notice to improve its accuracy. The most reliable method to determine the bulb size is by pulling your actual bulb(s) and reading the part number indicated directly on the bulb. The information compiled on this page comes with no guarantees or warranties.