The alternator charges the battery and provides your car with a constant source of electricity while the engine is running. Over time, the alternator can fail and cause problems with other electrical devices in the car.

The first thing to check is the battery light on the instrument cluster. This light bulb is part of the alternator field circuit; if it burns out the alternator will not charge. Simply turn the key on and see if it illuminates briefly then goes off. If the light does not illuminate, you’ll need to replace it before continuing.

Inspect the belt that drives the alternator. Is it tight and amply turning the alternator? If not, then check the condition of the belt, they seldom break, but they get brittle and glazed with age, and can slip on their pulleys. Replace the belt with a new one as required.

The next item to check is the voltage at the battery. This should read a little more than 12 volts with the engine off. Wait two minutes after starting the vehicle for (accessory cycling) voltage to stabilize. When the car is running, the voltage must read in the range of 13 to 14.5 volts with the engine at 3000 rpm.

Finally, check the ground strap itself and make sure it is connected and not damaged.

After checking the above and you’re still experiencing charging issues, it is likely the alternator will need to be replaced.

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Mark/Pelican Parts