Taking care of your alternator

When the alternator malfunctions or stops working it can mean expensive repairs, inconvenience or a break down. The alternator, which powers the vehicle’s electrical system and computers, not only provides current to operate all of your car’s electrical accessories and the engine – it keeps the vehicle’s battery charged. The battery’s job is to start the car, and the alternator keeps it running.

Cars today with their fancy headlights, navigation systems, stereo systems with multiple speakers, rear window defrosters, in-car television or DVD players, heating and air conditioning systems place extra work on the alternator and the battery which are then often hard pressed to keep everything functioning. Demands can often exceed the alternator’s capacity, leading to less performance from accessories – and ultimately to a dead battery.

Possible alternator warning signs:

  • Dim lights: If the alternator starts to give issues, you might notice your headlights and/or dashboard lights begin to dim or when the headlights start pulsating at night from dim to bright. Once the dash light or headlights dim, it is an indication of potential alternator malfunction. A waning alternator may cause other electronic accessories such as power windows and/or power seats to operate more slowly than usual.

  • Warning light: Most modern cars have a dashboard warning light that alerts you when the alternator is giving issues. This light may only trigger if you are using multiple electrical components. It is generally subject to how much life your vehicle’s alternator has left and how much electricity your vehicle is using.

  • Weak or dead battery: An alternator can only recharge your car battery to the point that it has a decent amount of life left in it and is able to accept a charge. If the battery is really weak or dead, the alternator cannot bring it back to life. To see whether the issue is the alternator or the battery, simply charge the battery and restart the vehicle. If the battery is weak the car will continue to run but the lights will become dim after a short time, indicating a problem with the charging system. If the vehicle has difficulty starting after the battery is fully charged, the problem is likely with the alternator.

  • Odd sounds: You may hear squealing noises in your car’s engine. There are many different parts that spin inside your vehicle’s alternator to produce electrical current. If one of these parts becomes worn or breaks, this could cause a grinding or whining noise. Worn out bearings inside the alternator have been known to cause this type of noise. If the bushings that the alternator is mounted on have gone bad a noise will be produced.

  • Weird smells: An alternator works in conjunction with a system of belts. If a belt is not turning freely the excess friction could cause the belt to heat up which produces a burning rubber smell. If you detect a smell similar to that of an electrical fire, this could indicate that the belt is slipping on the alternator pulley, causing poor alternator output. Tightening the belt could fix this. If tightening your belt does not fix the strange smell and alternator output we suggest having your alternator checked by a professional mechanic.

  • Visual cues: If you are experiencing problems with the electrical system the alternator might be fine as the problem could be with one of the belts connected to the alternator. We recommend you get a professional mechanic to perform a visual inspection of the engine compartment to determine if a belt is too loose or too tight or even cracked or worn.

An automotive service centre can check your vehicle’s electrical system, make sure the battery is fine and check the alternator output to make sure it’s operating properly. If the alternator is the issue, replace it or ask if the automotive service centre offers a re-manufactured one.