95 Buick LeSabre battery charging problems

[tomtrout]

When the engine is cold the battery light goes out as soon as the engine is started. After the engine warms up the battery light comes on. I have replaced the alternator and the battery. The battery terminals are clean and have a good connection. All the grounds are clean and have a good connection. I do not get the check engine light. Any ideas? Could it be the power control module that feeds the alternator?

[HotZ28]

Connect a voltmeter positive lead to the alternator B+ terminal and the negative lead to ground.
Turn all electrical accessories off.
With the engine running at 2,000 rpm, check the alternator output voltage. The voltage should be between 13.0 and 15.0 volts.

[tomtrout]

The voltage is between 13.0 and 15.0 when the battery light is off and about 11.7 when the battery light is on.

[HotZ28]

It sounds like you have a bad regulator in the alternator. I have seen new units fail soon after installing them. Take it and have it tested off of the car. Just as a precaution, be sure to disconnect the positive lead to the battery if you install another one!