How To Diagnose Common Volvo Alternator Issues

If you own a car, you might want to learn how to diagnose common issues so that you can get your car to the workshop before it actually breaks down. The alternator generates electricity to some parts of the system within a car and is a critical part of the system required to run the engine. Volvo alternators are generally reliable and durable, however, on occasions they might need a repair or replacement. There might be significant issues on the horizon for the car if the alternator starts to fail, thankfully there are some telltale signs which you can identify and solve Volvo alternator issues.

Alternator Unable To Charge

Volvo monitors the alternator output and will put on a battery warning light when the alternator output is too low causing battery to be unable to charge. However, this could be due a few reasons:

  • Alternator being worn out
  • Voltage regulator having issues
  • Internal short or break
  • Loose or missing fan belt


You may notice that the voltmeter on your dashboard to start off high on the readings and gradually settles back down, however, if the reading on the voltmeter reads overly high constantly, you may have an issue with the alternator. A primary way of diagnosing issue is by testing the voltage output of the alternator at a given revolutions per minute (RPM). Please bear in mind that overcharging could also be due to failed rotor or regulator, or due to poor battery conditions.

Noisy Alternator

When you start to hear a whining alternator, it could be due to a worn-out alternator bearing, which is often caused by an overtightened fan belt that is wearing down the unit. Unfortunately, replacement the bearing is a short-term solution which means the same issue might occur again. Therefore, it is advisable that you change the whole unit entirely. Other reasons that might contribute to a whiny alternator could be a loose pulley, or a loose or damaged fan belt.

Dim Warning Lights

The warning lights should glow brightly and subsequently extinguish when you switch the ignition and start the engine under normal charging system. Your alternator may be faulty if the initial warning lights appear dim or the warning lights fails to illuminate. There is a possibility that it may be due to a blown warning light bulb, loose fan belt, relay issue or loose wiring plug.

Continuous Warning Lights

As mentioned above, it is a sign that the alternator may be faulty if there are dim or no warning lights. However, should the warning lights be illuminated continuously, this could point to a whole host of mechanical issues. You might smell a hint of burning if the alternator is defective or there might simply just be an issue with the warning lights circuit.

It is necessary to identify some common issues so that you may get the necessary repairs done. An important tip would be to ensure that your battery is fully charged before replacing an alternator.