Your car has a list of crucial components that allow you to commute and make motoring as painless as possible. One such component is the alternator. Simply put, the alternator keeps your car's battery charged by using a pulley driven by the engine with a rubber belt. In this way, you can turn on your car and use its accessories, which require electricity.
Related: How to test an alternator
The alternator turns mechanical energy from the engine into electricity via induction. Wires within the unit undergo a magnetic field as they spin, which creates an electrical current, AC, to be exact. Over time, though, the alternator wears out and doesn't charge your battery or power your car's electrical system. Here are signs you can look for to potentially diagnose a bad alternator.
1. Battery Warning Light
This one can be confusing because you'd think there's an issue with your battery, but in actuality, this can mean there's an issue with the electrical charging system in your car. The warning typically appears when your alternator's voltage drops or exceeds the average 13-14.5 volts. Any electrical component you use in your car places a load on the alternator; now, if you have the battery light flickering on and off, this may indicate an issue with your alternator. You can check your alternator's voltage by using a multimeter.
2. Dead battery
Sometimes, your alternator may not be bad, but the battery could be kaput. Usually, this should be your first port of call before diagnosing a bad alternator. Batteries typically last around 5 years if their charge has been maintained. Yes, accidents can happen that will drain a battery's charge, such as leaving your headlights on or forgetting to turn off your radio. However, a battery charger or jumper cables can get you back up and running. Remember also that batteries need DC. However, in some freak instances, the alternator can drain the battery as a parasitic draw from a faulty diode.
3. Starting issues or stalling
If you have issues starting your car despite there being fuel and everything else needed to start a vehicle, it could mean your alternator is bad. This is characterised by hearing only a clicking noise instead of the car starting.
4. Weird smells and noises
If you smell rubber burning from the alternator's location, it could mean the belts are on their way out. A metal-on-metal burning smell could also mean the brushes and wires inside the alternator are finished. Whirring noises can also mean the unit is finished.
5. Malfunctioning electronics
If you notice flickering headlights, slow electronics like electric windows moving slowly, or fan blowers being dulled, your alternator may not be charging properly.
6. Loose or broken connections
If you're done troubleshooting and still have no solution, check the connections on the alternator and your battery. A loose connection can cause your car's computer to throw errors. The alternator is grounded, so loose or bad ground cables and points can also cause it to not charge properly.
What can I do if my alternator is bad?
Alternators can be expensive and laborious to replace, but they are a crucial component. There are a few ways to sort a bad alternator, with varying costs.
- You can go with a brand new original alternator (Expensive)
- A refurbished original unit is a good way to go about this, as you can replace finished brushes and wires in the alternator with new ones. (Reasonably priced)
- Good aftermarket replacement units (Decently priced)
- Used option (Can both be affordable and expensive if the used unit also fails quickly.)
