Car Won’t Start and Check Engine Light Is On

Possible Causes

Dead battery
Faulty starter
Bad alternator
Fuel pump failure
Ignition switch problems
Faulty spark plugs or wires
Clogged fuel filter
Computer problems

Troubleshooting

Check the battery. Make sure the battery terminals are clean and tight. If the battery is dead, you can try jump-starting the car. If the car starts, but the check engine light is still on, you should have the battery tested by a mechanic.
Check the starter. If the starter is not engaging, you can try tapping it with a hammer. If the starter engages, but the engine does not start, you may need to replace the starter.
Check the alternator. The alternator is responsible for charging the battery. If the alternator is not working, the battery will eventually die and the car will not start. You can check the alternator by using a multimeter to measure the voltage output. If the voltage output is below 13 volts, the alternator may need to be replaced.
Check the fuel pump. The fuel pump is responsible for delivering fuel to the engine. If the fuel pump is not working, the engine will not start. You can check the fuel pump by listening for a humming sound when you turn the key to the “on” position. If you do not hear a humming sound, the fuel pump may need to be replaced.
Check the ignition switch. The ignition switch is responsible for sending power to the starter. If the ignition switch is not working, the starter will not engage and the engine will not start. You can check the ignition switch by using a multimeter to measure the voltage output. If the voltage output is below 12 volts, the ignition switch may need to be replaced.
Check the spark plugs and wires. The spark plugs are responsible for igniting the fuel in the cylinders. If the spark plugs are worn or damaged, the engine will not start. You can check the spark plugs by removing them and looking for signs of wear or damage. If the spark plugs are worn or damaged, they should be replaced.
Check the fuel filter. The fuel filter is responsible for removing impurities from the fuel. If the fuel filter is clogged, the engine will not get enough fuel to start. You can check the fuel filter by removing it and looking for signs of clogging. If the fuel filter is clogged, it should be replaced.
Check the computer. The computer is responsible for controlling the engine’s operation. If the computer is not working, the engine will not start. You can check the computer by using a diagnostic scanner to read the trouble codes. If the trouble codes indicate that the computer is not working, the computer may need to be replaced.

Conclusion

If you are unable to fix the problem yourself, you should take your car to a mechanic. The mechanic will be able to diagnose the problem and perform the necessary repairs.