Malfunctioning Alternator

The alternator is just as essential as the battery. Not only does it recharge the battery, but it also provides electrical power to the vehicle when the engine is running. On a basic level, the alternator converts mechanical energy from the engine into electric energy that powers your lights, sound system and other electronics.

Common symptoms:

• Power warning lights while you're driving

• Signs of changes to the electricity supply in the car, like lights that dim and then get bright

• Electrical components (e.g., the radio or windows) losing power

• The vehicle is stalling, and a jump-start won't restart it.

• Grinding noise that changes as speed changes

• Burnt rubber smell

Faulty Starter Motor

The starter motor is a small electric motor that's powered by the battery and turns on the internal combustion engine when the key is turned. If your starter motor isn't working, your engine can't spring to life.

Common symptoms: If your starter motor is dead, you'll hear a clicking noise when you turn your key, but the engine won't turn over. Alternatively, if you hear a whirring noise when you turn the key, you might need to replace the starter solenoid.

Causes:

Starter issues can be caused by faulty wiring, the breakdown of mechanical parts in the starter motor, dirt and rust or even oil leaks. Understanding what caused your starter issue can help you avoid it in the future.

Tips to prevent a faulty starter motor:

• Control battery corrosion, or replace corroded batteries. The corrosion can spread to the starter, impacting its function

• Keep your battery and fuses functioning well, and replace them when needed.

• Avoid stopping and starting frequently, which can wear down the starter.

Bad Spark Plugs

Spark plugs give your vehicle the power it needs by converting electric energy into a spark that ignites the fuel and powers the engine. They kick-start the chain reaction that powers your car, so when they're not working, lots can go wrong.

Common symptoms:

• Engine trouble, including vibrations and trouble idling

• “Check engine" light (either flashing or solid)

• Decreased gas mileage

• Power surges and drops

Causes: Spark plugs wear out over time.

Wiring Problems

Like an electrical system, your car relies on wires to get electricity where it needs to go. When something goes wrong with wiring, even finding the problem can be difficult. Once you know where the trouble lies, you'll need to replace the damaged or broken wires.

Common symptoms:

• Flickering lights or occasional power loss

• Smell of burning plastic, or other signs of melting or heat

• Issues with starting your car

• Frequently blowing fuses

Causes: Anything that interrupts the electrical circuit can lead to wiring problems in a vehicle. Some common causes include rodents chewing on wires, corrosion and wires that come loose over time.

Engine Control Module Failure

The engine control module is a computer that controls your engine. Without it, the engine won't start. Sometimes, this is called the engine control unit or powertrain control module. No matter what name it goes by, it's essential for modern cars.

Common symptoms:

• Car won't start

• "Check engine" light turns on

• Frequent stalling and poor running when the car does start

Dead Battery

The battery is the heart of a vehicle’s electrical system—the system can't function without it. Car batteries charge while the engine is running and must hold that charge when the engine is off. Sometimes, batteries drain for obvious reasons, like when the lights, or sound system are left on. In that case, you can jump-start them back to life. However, if your battery isn't able to hold a charge, you'll need to replace it entirely.

Common symptoms:

• Engine not turning over immediately

• Dim interior lights

• Battery warning light turning on when you're driving

• Car stalling

Causes: Batteries lose efficiency over time. Most car batteries last for about three to five years, so this is a part you'll have to replace regularly.

Tips to prevent dead batteries:

• Take long trips and run your car regularly. Batteries recharge while the engine is running, so taking regular drives will keep it functioning well.

• Avoid excessive heat. Heat makes batteries die faster. Unfortunately, there's not too much you can do if you live in a hot climate where batteries generally have shorter lifespans.

• Secure it tightly. Vibrations can make a battery die quickly. Use hardware to hold your battery in place, and avoid rough roads when possible.

Causes: Alternators have lots of wearing parts (including bearings and belts) that are under constant strain. It's normal for them to give out over time.

Bad Fuse Box

Fuses protect your car's electrical system by melting, if too much electricity flows through them. For ongoing electrical issues, you may need to replace the whole fuse box. Most cars have two—one under the hood and one on the driver's side of the cabin.

Common symptoms: If a fuse is blown, you'll notice that a certain circuit, like the radio, doesn't have power. Signs that you need to have replace the fuse box include:

• Frequently failing fuses

• Fuses that are loose

• Broken or bare wires

• Water stains on the fuse box