Possible electrical system malfunctions that prevent the car from starting:
1. Battery:
*Dead battery
* Poor contact between battery terminals and wires
*Corrosion or damage to battery terminals
2. Starter:
* Faulty retractor solenoid
* Seized or worn starter
* Poor contact between starter and battery
3. Ignition system:
* Faulty engine control module (ECU)
* Faulty crankshaft position sensor
* Faulty ignition coil
* Faulty spark plugs
4. Fuel system:
* Faulty fuel pump
* Clogged fuel filter
* Fuel leak
5. Vehicle electrical system:
* Break in electrical wiring
* Defective fuse or relay box
* Faulty alarm or immobilizer
6. Other possible reasons:
* Insufficient fuel in the tank
* Frozen fuel
* Problems with the mechanical part of the engine (for example, seized engine)
Diagnosis and troubleshooting:
* Check the battery: Measure the battery voltage and make sure it is above 12 volts. Inspect the battery terminals, clean them if necessary.
* Check the starter: Listen for the click of the retractor solenoid when you try to start the engine. If there is no click, the solenoid may be faulty. Try tapping the starter with a hammer to free it from being stuck.
* Check the ignition system: Make sure there is spark at the spark plugs. Use a tester to test the ignition circuit.
* Check the fuel system: Turn on the ignition and listen to see if the fuel pump is working. Check the fuel filter for blockages.
* Inspect the electrical system: Check fuses and relays for blown or damaged ones. Inspect electrical wiring for breaks or exposed wires.
*Check for other possible causes: Make sure there is enough fuel in the tank, that it is not frozen, and that the engine is not seized.
If you are unable to locate and repair the problem yourself, have it diagnosed and repaired by a qualified mechanic.