I bought a light bulb with the CANBUS system and I still have a burned out light bulb error:

The CANBUS system is called the same on all cars, but there is no standard for this system. Each brand configures the system with a different sensitivity, even differences are found in one brand but in different car models.

The bulbs we offer work well in most cars, but there are particularly picky cars.

In fact, we only have 100% certainty after installing the bulb; then we know if it fits or if the error is displayed.

The capricious models are especially the VAG group:

Audi A4 B7

Indoor bulbs work smoothly, bugs are found with any outdoor lighting bulb.


Filters / resistors application.

Audi A3, A6, S series

daylight bug


Filters / resistors application.

Seat Leon 1P from MY2011

error in the case of daytime running lights, direction indicators


Filters / resistors application.


Non-polarized bulbs, shine in any position without + and - restrictions in the car.


Built-in electronics do not show a combustion error in 98% of cars with CANBUS.

H4 is off or only one light is on:

Only after the appearance of LED bulbs, it turned out that already in the car production stage there are often places where the + and - cables supplying the bulb are changed. In the case of traditional incandescent bulbs, it doesn't matter at all, but when using LED bulbs it is important that the connection is correct.

In the case of the H4 bulb, it is usually sufficient to swap two wires supplying voltage to the bulb, replacement is simple because, as a rule, all you need is a screwdriver and change the terminals. It is these two parallel ends. The photo shows how the power supply should be connected.

What light bulb is in my headlight?

Car manufacturers install different headlights on a car model, which differ in terms of design. It depends on the version of the equipment, the options requested, the market for which the copy was destined and other factors that only the manufacturers know. For used cars, the previous owner may have made the modification.

Therefore, before buying, please check what type / model of bulbs have been used in the vehicle

Do I have an HB3 or HB4 bulb?

The HB3 and HB4 bulbs are almost identical, the difference is in one place. At the socket.

In the case of the HB3 bulb we have two guide rails at the top,

And there is a rail in the HB4 bulbs. This is the only difference.

I bought a W21W / 5W - 7443 bulb, it burned out immediately after putting it in

The problem lies in the incorrect connection of the cables in the socket. Control of which fiber should shine should be more + and mass - should be shared by two fibers. Now it turns out that when customers change the bulbs from ordinary to LED, these connections are not always correct. For a conventional incandescent bulb, there is no difference, but for LEDs it is important to connect the wires correctly. Incorrect connection, the bulb burns out almost immediately. Such damage is not subject to warranty replacement. Therefore, check whether we have the correct connection of plus + and ground - cables.

The difference between H8 and H11

The bulbs look almost identical, but there is a slight difference. Each of these bulbs has 3 wings that we plug into the socket and rotate to connect the bulb. For H11 bulbs, the left and right wings are narrow and the central wing is wider. In the case of the H8 bulb, the left wing is wider than the others. The width difference is about 2mm.

Where is the purchase document and warranty?

Based on the information displayed when placing the order and sent to the customer by email, the documents are sent electronically by email.