Possible reasons:
* Disconnected battery:
* Check if the battery terminals are loose or disconnected.
* Clean the terminals from any corrosion or dirt.
*Tighten the terminals tightly.
* Defective or discharged battery:
* Check the battery voltage using a voltmeter.
* Replace or recharge the battery if necessary.
* Faulty generator or regulator relay:
* The generator is responsible for powering the electrical systems, while the regulator relay controls the voltage supplied by the generator.
* Have the generator and regulator relay diagnosed at a car service center.
* Faulty fuses or relays:
*Check the fuses and relays in the under-dash fuse box or in the engine compartment.
* Replace blown fuses or faulty relays.
* Broken or damaged electrical wiring:
* Check the wiring from the battery to various electrical components such as the engine, lights and radio.
* Inspect the wires for signs of breaks, damage or corrosion.
* Faulty engine control unit (ECU):
* The ECU controls various engine functions and electrical systems.
* Diagnose the ECU at a car service using a fault code scanner.
* CAN bus problems:
* CAN bus is a network that connects various electronic modules of a vehicle.
* Failure of the CAN bus may cause electrical systems to malfunction.
Steps to resolve the problem:
1. Check the battery and battery terminals.
2. Check fuses and relays.
3. Inspect the wiring for damage.
4. Try to start the car using jumper wires (if another car is installed).
5. Contact a car service to diagnose and repair more serious problems, such as a faulty generator or ECU.