The light fixture stopped working.

Is the fixture 120, 240,208 480 volt? Need a little more on model number. Is it 400

You must be using EU standards for electricity. Earth and N are the same. L is load.

However, I can provide guidance on using a basic voltage tester to check for live wires when troubleshooting a light fixture installation.
Using a Voltage Tester:
Non-Contact Voltage Tester:
If you have a non-contact voltage tester, it's a handy tool for quickly identifying live wires without direct contact. Hold the tester close to the wire insulation or the terminal screws, and it should indicate the presence of voltage without making physical contact.
Contact Voltage Tester:
If you have a contact voltage tester, make sure it's designed for the voltage level you're working with (e.g., 120V for residential electrical systems).
Turn off the strength to the circuit on the circuit breaker or fuse box.
Safety First:
Always prioritize safety. Make sure the power is turned off before working on any electrical components.
Test the Tester:
Test the voltage tester on a known live circuit to ensure it's functioning properly.
Check the Wiring:
Once confirmed, turn off the power to the circuit you are working on.
Use the voltage tester to check each wire connected to the light fixture. Verify that there is voltage on the wires.
Neutral and Hot Wires:
Typically, a light fixture will have a hot wire (usually black) and a neutral wire (usually white). Make positive each wires are linked properly.
Ground Wire:
Check for a ground wire and ensure it's properly connected. Some light fixtures may have a green or bare copper wire for grounding.
Switch Position:
Ensure that the wall switch controlling the light fixture is in the ON position.
Bulb Check:
Confirm that the light bulbs in the fixture are working and properly installed.
Circuit Breaker Check:
Double-check the circuit breaker or fuse for the lighting circuit to make sure it hasn't tripped or blown.

With the power off, make sure the connections are correct and tight. Check the fuse/circuit breaker and switch in that order.

Is it a new installation? Your ceiling fan should never trip a breaker unless it has a problem in the fan or light fixture attached to it.

replace the ballast almost always these lights do not usually burn out the ballasts go bad

Do me a favor, prior to reading on any further; did you try pulling (or turning) on the fan chain? As simple as this sounds, I've experienced this before. And I'd rather you try the simple solution first, before opening up the fixture. Okay, if that didn't work - the first TURN OFF the light switch or circuit breaker before working on these fixture's. If you're not well schooled in doing electrical work, I'd advise turning the circuit breaker off along with the wall switch. Now, when you open up your fixture, the black wire should be hooked up to the fan motor(s) lead wire; and the blue wire to your light(s) lead wire. Now, if both your fan and light were working before, then the wires at the fixture (black/motor and blue/light) were wired together. If so, then it could've blown both motor(s)? But I don't believe it did. Now that you've checked everything out, and your ready to turn the fixture back on. Keep the wall switch in the off position. Then go turn on your circuit breaker. If everything holds, then turn the wall switch on. It's done in this manner for safety reason's. Try this, and then let me know how it went. You should be good to go. Good Luck, and feel free to contact me again if you have any problems. Jim

hello, all you have to do is to get a new breaker with the same amperage or amp's example 15 amp's of the breaker that's blown and pop out the old one and put in your new one , in the future when working with electricity always manual trip the breaker before working for your safety and the safety of the equipment .good luck

Open neutral. check the fixture/switch closest to the bkr panel that is not working for a bad connection in a wire nut, if not there, move to next fixture/switch closer to the panel