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1998 Mazda 626 - Charge light

My car will be 22 years old on December 8. I have been buying it gasahol for all these years and now that it will be a year older than the legal age to buy alcohol, shouldn’t it be buying its’ own gasahol? But seriously, the battery charge light has been flickering occasionally and I suspect the voltage regulator is at fault. The battery is less than a year old and the car has 91,480 miles on it. Could there be another cause for the light to be coming on or should I just get a new alternator/voltage regulator?

Don’t just guess… measure first to determine the problem. Just throwing parts at the problem might work, might not.

The battery voltage should be about 12.4 to 12.9 at rest, car off. The voltage with the car running should be at least 13.5 volts. If it is not, the alternator is a likely culprit. The regulator is inside the alternator so no seperate parts. The voltage should hold no matter what rpm and accessory load. Turn the AC on, the voltage should maintain.

When the serpentine belt is removed, check all the tensioners and their pulleys. If the voltage drops when you turn on the AC or rev the engine up, the belt could be slipping and causing your problem.

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