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Buick Alternator Troubleshooting

Does your battery charging light flash intermittently? How many volts should your alternator deliver to charge your battery? An automotive alternator is the lifeblood of an automobile’s electrical system which generates electrical energy from mechanical movement. Solutions to alternator problems are often beyond the reach of the average users’ knowledge. In such cases, Experts are available to assist with Buick alternator problems.

Some situations calling for Buick alternator repair are cited below as questions from users. Read how verified Experts have answered them.

How to troubleshoot a Buick Rendezvous with a new battery when the battery light flashes at speeds above 50 mph?

Since the battery is new, chances are the alternator is faulty and does not seem to be able to deliver adequate voltage at high speeds. Check that all connections to battery terminals and alternator are clean and secure. Run the car again and if the battery light still flashes an alternator replacement appears to be the solution.

How to fix a Buick alternator where the voltage is good when starting but drops when the engine has warmed up?

Case Details: The observations are based on dashboard gauge readings.

Using a voltmeter, check the voltage at the battery with the engine off and when it is idling. Also check it again after the engine has warmed up. If, when running, the voltage remains above 13 volts the alternator performance is barely acceptable, but weak. This is not unusual with replacement aftermarket alternators if one is installed on this car. If the voltage is above 14 volts and the gauge inside the car reads less, then the dashboard gauge is suspect.

Why does the battery warning light come on and the voltage drop at random when a Buick is on the road?

This is typical of a bad alternator which needs to be replaced. The alternator is tasked with charging the battery and when it does not, the battery warning light comes on. The light indicates that the charging rate is too low, typically 13 volts and below. Have the alternator tested, and if defective replace it before it can damage the battery.

Why does a Buick LeSabre battery drain overnight when the alternator delivers 15 volts?

The charging rate of a good alternator is between 14.4 and 14.6 volts; therefore, 15 volts is marginally high. However, chances are that the battery is draining because of a parasitic draw. Ask an online Expert how to check for a parasitic draw. If the test proves negative and there is no draw, then the alternator is over-charging, placing the battery at risk.

How has a Buick Rendezvous run through two batteries in quick succession?

Assuming the connections to the battery and alternator are good, and there is no parasitic draw on the battery, and that all its cells are good, the problem boils down to a failing alternator. An alternator has to recharge the battery when the car is running and this has to be done at a specific voltage and amperage. Anything outside the specified range will damage the battery or cause some other problem. Have the alternator tested and if it’s performance is bad, replace it. Just to be certain, however, repeat the draw test to make sure none of the electrical features are draining the battery. A parasitic draw is equally harmful to a battery and can shorten its life.

Why do the head and tail lights on a Buick LaCrosse pulsate?

A problem like this happens most often because of a failing alternator. Check all the connections to the battery and alternator, then load test the battery itself. If it all checks out OK then the alternator appears to be on its way out.

Why does the voltage across the battery of a Buick Rendezvous CXL suddenly surge?

A sudden jump in voltage would be due to a faulty voltage regulator within the alternator. GM has released a TSB about replacing the regulator and wiring harness for the alternator on this vehicle.

A car alternator appears to be simple straightforward element in a car’s electrical system, but it can be complex to one who does not understand it’s working, especially when a problem arises. This is where it pays to consult a verified automotive electrical Expert abreast of the latest developments in alternator technology. An online Expert will provide answers to any Buick alternator issue. This service is available to you in the privacy of your home.

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