CANBUS is a technical standard, which was born in the early 2000s. Now almost all cars are in use. It has many functions and can completely and automatically detect any burned bulb. On CANbus, when the bulbs burn out, the car itself will notice them and indicate them to you through the message on the instrument panel.
When you replace the original incandescent bulb with an LED bulb, the car may not recognize it and send a message on the instrument panel immediately. This seems to be a kind of "error!!"
New ofCANbus LED bulb has electronic equipment that can be recognized by CANbus automobile; This way, you won't have any error messages or lighting faults on the dashboard. It is indispensable for cars produced in recent ten years! Therefore, you can install these LED lights without worrying, because the car CANbus will recognize them without reporting abnormalities.
You have chosen the right LED bulb for yourself, but you find yourself struggling with the CANbus system. CANbus may have problems when you replace the bulb and install the LED bulb in the brake light.
Reasons why some LED lights cannot be used with CANbus
The LED lamp is not suitable for CANbus because the current consumed by the LED bulb is small, so the control unit reads the low working power from the bulb and responds to the CANbus system incorrectly. The control unit turns on the burnt out headlights and even stops the power supply by turning off the components: This is for safety reasons.
To solve this problem is very simple, usually just place a resistor in the circuit. However, in view of the wide variety of LED bulbs, to determine the results, you need a tester, patience and measurement.
How to measure and calculate
I will show you the steps I follow to purchase a resistor so that you can always find the right resistor for you when you replace any bulb (low beam, high beam, stop or use LED bulb)
Let's start by measuring the current required by the original bulb. We'll replace it with an LED. To measure amperes, connect the tester in series to the bulb and turn it on, preferably with the car on.
The same procedure must also be performed for LED bulbs. Since you are there, you have to check the voltage by connecting the tester in parallel.
All these measurements are made with the engine running and may be made at high idle (2000 - 3000 rpm) because the voltage changes and it is easy to obtain much more voltage than the classic 12 volts. Many times, at high speed, it even reaches 14.5 volts.
Now that you have all the data you need, let's calculate. We calculated the wattage of the LED bulb and the original bulb (don't trust the things written on the bulb, it's best to calculate with the instrument data). So now, we can track the resistance of two circuits: LED circuit and filament circuit.
We can finally get back to the resistance we have to buy. What we need is to install in our specific situation without trying many times, so we can directly achieve the goal!
When you install resistors that dissipate a large amount of current, you must put them in the right place. It is better to put the resistor in a metal place rather than a plastic place.
