What Are The Symptoms Of Charging System Failure?

The charging system in your vehicle is critical to its operation. However, many common issues, such as the battery or alternator, can make the charging system failure. Issues that affect the charging system need addressing as soon as you know you have a problem or you may find yourself stranded with a car that will not start or run.

What Is The Charging System?

Made up of the alternator, battery, wiring, and electronic control unit (ECU), your vehicle’s charging system keeps your battery charged. It also delivers the energy necessary to run the lights, radio, and other electrical components while the engine is running.

Whenever this light goes on, it means that the vehicle is running solely on battery power. If the problem continues and your charging system fails, the battery won’t be able to recharge and it will soon run down, leaving you with a dead battery. Nothing can ruin a day like a dead battery, so if this light comes on, it’s time to take your vehicle to your trusted mechanic to have them find the source of the problem.

Please note that depending upon your vehicle, you might have a battery light and check the charging system light. Check your owner’s manual to learn what warning lights your car has.

Symptoms Of Charging System Failure

The signs that of failure in the charging system are just as you might expect. Since your car relies on battery power to run, or even to turn on the lights inside the cabin when the charging system fails these functions seize to work properly. Being aware of what to look for when your charging system encounters a problem can help you fix the issue before it progresses and you’re left without a working car.

1. Loss Of Power

Of course, losing power is the number one symptom of charging system failure. You might experience problems with dim or flickering lighting inside the cabin or your headlights may become dimmer too. Certainly, you’ll not be able to start the car if you lose power totally.

2. Charging System Light In-Dash

Some cars have a warning light inside the dashboard that illuminates when the charging system begins experiencing issues or complications. With each year that passes, these warning systems advance, and technology supports more accurate diagnoses while reading these trouble codes. You’ll need to bring your car to a mechanic to read and clear the warning light.

3. Battery Dies

A dead battery could mean several things, and it’s safe to assume that it’s not just the battery that’s running into problems. If a battery can’t hold a charge, then it might need to be replaced; however, it could not be receiving a charge in the first place, which will lead your technician down an alternate route of treatment.

4. Charging Issues

When diagnosing the causes of charging system failure in your car, your automotive technician must perform a thorough differential diagnosis. Since charging system problems can be due to several areas that are struggling, it’s important to rule out the causes one by one to avoid fixing or replacing the wrong part.

5. Alternator

As your car drives, the alternator is responsible for recharging the battery. The power the alternator translates to the battery is important for the battery to hold a charge, and if the alternator isn’t doing its job then the battery will eventually die.

6. Battery

Of course, power issues can be traced back to a faulty or malfunctioning battery. It’s important to regularly check the health of the battery and keep it in good working order by using insulation kits, cleaning the terminals, and replacing it when it’s time to.

7. Wiring

Since the charging system utilizes wiring to transfer and transmit power, it’s critical that wiring is kept in good working order. Damaged wiring is not uncommon in cases where the failure of the charging system occurs, and it’s usually an easy problem to fix.

How Do You Fix A Car Charging System?

If you are experiencing any of these problems, here are some helpful tips that will help you troubleshoot your vehicle’s alternator charging system.

1. Conduct A Visual Inspection

Inspect belt condition and tension. Ensure it’s not worn, cracked, loose, or glazed. If that checks out, examine the electrical connections and cables for signs of corrosion and proper firmness. Lastly, ensure the alternator is correctly fixed.

2. Visually Inspect The Batteries

Examine the batteries for any indication of physical damage, broken casing, unfastened terminals, or dripping fluid. If you encounter any of these signs, clean, repair the connection, and change any damaged batteries found. It is, however, important to keep in mind that all the batteries used in the circuit are of the same age, cold-cranking amps rating, and from the same manufacturer.

Next, carry out a battery test using the standard battery test method. Bear in mind that for realistic testing as well as a successful operation. You will require a completely charged battery that will be able to supply the starting system’s needs.

3. Perform a System Voltage Test

The other step to troubleshoot the alternator charging system is to measure the voltage of the battery while the engine is running using a voltmeter for accurate results. If the recorded voltage is higher or equal to 13.8 volts, you can test the alternator output.

However, if the voltage is less than 13.8, determine the voltage at alternator B+ and the alternator ground case. Keep in mind that if the model is insulated, you have to use a ground stud to get a reading. In addition, if the alternator has a remote sense, the voltage at the alternator could be more than 15 volts.

Now, if the voltage is between 12.6V and 13.7V, it’s time you change your alternator. However, if the voltage is greater or equal to 13.8, perform a voltage drop test.

4. Test Alternator Output

Performing an alternator load test ensures that the alternator is providing sufficient current for operating the vehicle’s electrical loads and maintaining battery charge. To perform alternator output tests, you can employ the automated tester method or the manual process. To perform the manual process, you will need a Carbon Pile tester, an Ammeter, and an Amp Clamp.

First, connect the carbon pile tester to the battery. The positive or red lid connects to the positive post and the negative or black lid to the negative post on the battery. Then clamp the ammeter in the correct polarity around the B+ cable near the alternator.

Now with the engine running at governor speed and all electrical loads turned off increase the load of the carbon pile until the ammeter reads its highest value. Record the output and turn off the carbon pile and engine. Amp output should be at least 90% of the rated capacity. If it’s not, that is a clear sign that the alternator needs replacement.


Driving with your battery, check the charging system light illuminated could leave you stranded. If your vehicle has a failing battery, faulty alternator, or bad wiring, it could stop working at any time. Make an appointment with your mechanic before your car puts you on the side of the road.

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