Signs of car alternator failure and how to fix it

Your car’s alternator does the important job of keeping the battery charged while the engine is running and supplying power to all the electrical parts of the car like headlights, power windows, etc. When the alternator begins to fail, the car may suddenly stop or the electrical system may fail, leaving you stranded on the road.

Many drivers mistake this for a battery problem, but it is actually the alternator that is responsible. Big expenses can be saved by timely identification and repair. Alternator usually lasts for 1 to 1.5 lakh kilometres, but bad driving habits, heat or bad belt can wear it down quickly. Let us know how a bad alternator can be identified and what is the way to fix it?

What is alternator and why is it important?

The car’s alternator converts the engine’s rotational motion into electricity. After the engine starts, the battery energy starts draining, but the alternator keeps recharging the battery continuously. If the alternator does not work properly, the battery gets discharged and the car stops running.

In a country like India where there is heavy traffic and long driving, alternator problems are common. Heat, dust and bad road conditions affect it quickly. If you have the problem given below, then it is a sign of alternator failure-

Battery warning light on dashboard: This is the most common sign. If the battery icon or ALT/GEN light is lit, the alternator is not charging the battery properly. Sometimes the light also flickers. Many people ignore this as just a battery problem, but it could also be an alternator warning.

headlights and other lights becoming dim or too bright: When the alternator becomes weak, the power supply becomes unstable. The headlights sometimes shine very slowly, sometimes very brightly. Interior lights and dashboard lights may also flicker. This can be very dangerous while driving at night.

Car not starting or stalling repeatedly: If the car repeatedly won’t start or the engine stops after a few minutes of starting, the alternator is not able to charge the battery. If the car stops after some time even after jump starting, then the alternator is bad.

Problems with electrical accessories: Power windows opening slowly, music system stopping suddenly, AC becoming weak, seat heater or other electronics not working properly indicate alternator problem.

Strange sounds: When the bearing inside the alternator gets damaged, sounds like grinding, whining or screeching are heard. If you hear a screaming or growling sound coming from near the engine, get it checked immediately. Sometimes there may also be a smell like burning rubber, which is caused by slipping of the belt.

Frequent battery discharge: Even after installing a new battery, if it is deteriorating quickly, then the problem may be in the alternator. The alternator is not charging the battery, so the battery continues to weaken.

Degradation in engine performance: Slowing down or feeling vibration when accelerating the car can also be a sign of alternator failure, because the spark plugs are not getting enough electricity.

How to test alternator at home?

Stop the engine and check the voltage at the battery terminals. A good battery should have approximately 12.6 volts.
Start the engine and check again. If the voltage is between 13.5 to 14.5 volts, the alternator is working fine. If it is less than 13 volts or more than 15 volts, there is a problem.

Due to alternator failure

1. bad or loose drive belt
2. Wear of internal parts such as brushes, bearings or voltage regulators.
3. Overheating, water or oil ingress
4. Wiring problem or blown fuse
5. Installing excessive electronic accessories that place additional load on the alternator

How to avoid alternator problems?

Regular maintenance is the best solution. Get serviced every 10,000–15,000 km. Check the condition of the belt, keep the connections clean and do not allow dust to accumulate on the alternator in high-heat areas. If your car is old or driven a lot, regular checking of the charging system is necessary.

The cost of alternator repair or replacement can range from Rs 5,000 to Rs 20,000 depending on the model. But if timely attention is not given, the battery, electrical parts and even the engine can be damaged. If you notice any of the symptoms mentioned above, immediately go to a mechanic or service center. This will not only save your time, but will also prevent accidents on the road.