How to Fix Common Electrical Problems in Your Car Without Paying For An Expensive Mechanic

Having electrical issues with your car can be frustrating and expensive if you take it to a professional mechanic. However, with some basic tools and knowledge, you can often diagnose and fix many common electrical problems yourself for a fraction of the cost.

Understanding Electrical Systems in Your Car

Your car has several electrical systems that work together to power all the components, like the engine, lights, radio, power windows, etc. The main systems include:

• Battery - provides initial power to start the engine and run accessories when the engine is off. The battery is recharged by the alternator while driving.

• Alternator - generates electricity to recharge the battery while the engine is running.

• Starter motor - starts the engine by turning it over when you turn the key or push the start button.

• Ignition system - provides timed high-voltage electric current to ignite the fuel/air mixture in the cylinders. This allows the engine to run.

• Lighting system - powers the headlights, brake lights, turn signals, interior lights.

• Electrical Control Units (ECUs) - control different systems, like fuel injection, ABS brakes, power windows, etc.

Knowing the basics of how these systems work and connect together will help you diagnose issues.

Common Electrical Problems and DIY Fixes

Here are some of the most frequent electrical issues you may encounter and how to fix them yourself:

Dead Battery

A dead battery is the most common electrical problem. Likely causes include:

• Leaving interior lights on overnight drains the battery
• Battery is old and can no longer hold a full charge
• Alternator is not properly charging the battery while driving

Fixes:

• Jump start the car and drive for 30 mins to recharge the battery
• Load test the battery at an auto parts store - if it's bad, replace it
• Check the alternator belt tension and output voltage - replace if needed

Battery Corrosion

Corrosion on the battery terminals can prevent a good connection.

Fix:

• Remove corrosion with a wire brush or baking soda/water solution
• Clean terminals and battery cable ends
• Apply dielectric grease to prevent future corrosion

Faulty Alternator

If the alternator stops charging the battery, the car will eventually stall once the battery charge is depleted.

Fix: Test alternator output voltage. Replace alternator if it's not producing around 14 volts.

Bad Starter

If you hear clicking when trying to start, the starter motor is not turning over the engine. Causes include:

• Weak battery
• Faulty starter motor
• Loose or corroded wiring connections

Fixes:

• Check battery voltage and connections
• Test starter circuit for power - if no power, trace wiring and replace bad connection/wire
• If starter has power but doesn't turn, replace it

Faulty Spark Plugs/Wires

Problems with ignition components can cause misfiring, stalling, or poor performance.

Fixes:

• Inspect spark plugs - replace if fouled, badly worn or with large gap
• Check spark plug wires for cracking or loose connections and replace if needed

Electrical Shorts

Bare, crossed or pinched wires can create shorts in the electrical system and blow fuses.

Fixes:

• Inspect wiring harnesses throughout the car for damage
• Shake wiring while monitoring for shorts with a test light
• Repair or wrap any bare wires with electrical tape

With some basic diagnostic tests and repairs, you can solve many electrical issues on your own. But if the problem persists, seek help from a qualified mechanic. Paying for expert diagnosis the first time could save money and hassle over repeatedly trying DIY fixes.