Possible reasons:
1. Battery problems:
* Low battery
*Corroded or loose battery terminals
* Battery malfunction
2. Generator malfunction:
* Damaged rotor or stator
* Broken drive belt
*Voltage regulator malfunction
3. Problems with the electrical system:
*Blown or blown fuse
*Short circuit
*Main relay fault
* Damaged wiring
4. Ignition fault:
* Faulty ignition switch
* Faulty main relay module
5. Other reasons:
* Faulty crankshaft position sensor
* Triggered anti-theft system
* Ground problems (poor grounding)
Diagnostics and troubleshooting:
1. Check the battery:
* Measure the battery voltage should be around 12.5-13.5 volts.
* Clean and tighten the battery terminals.
2. Check the generator:
* Measure the system voltage with the engine running. It should be around 13.5-14.5 volts.
* Check the drive belt for damage or looseness.
3. Check fuses:
* Locate the fuse box and check if any fuse is blown. Replace blown fuses.
4. Check electrical wiring:
* Inspect the wires for damage, cracks or burns.
5. Check the crankshaft position sensor:
* If the sensor is faulty, the engine will not start.
6. Check the anti-theft system:
* If the system is activated, it may cut off power to the vehicle.
7. Check grounding:
* Make sure all grounding points are tight and clean.
If you cannot fix the problem yourself, have it diagnosed and repaired by a qualified mechanic.