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We put a volt meter across the battery and it showed 12.7 volts with the car off. We turned on the car and there was no change. Then we revved it up to about 2k-3k RPMS. Then the volt meter showed 14.3 volts. Is this normal???

A little more history:
It all started when I was leaving late one night. I went out and started the car to let it warm up and went back in. I came out about 10 minutes later and put some stuff in the car and the ABS and brake lights were on. I thought that's strange and I went back in to the house. About 5 minutes later I went back out to leave and the car had stopped running. I went to start it again and it would not start(it would only click). So I decided to stay there and not drive it. A couple days later I charged the battery and drove it home. I assumed that the alternator was bad so I tested it by disconnecting the positive battery cable and the car died. So I removed the alternator and had it tested at a local parts store. It came up good according to their test. I went back and put back in the car and did the test at the beginning of the post.

Also note worthy: The generator light(battery symbol on the dash) does not come on when you turn the key to the on position.
 

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180 Degrees out of faze
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Kind of sounds like the voltage regulator is failing. The light on the dash should be on whenever the key is on, and the motor is stopped.
 

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Never remove a battery cable with the engine running

NEVER, REPEAT, NEVER REMOVE THE BATTERY FROM THE VEHICLE CIRCUIT WHILE THE ENGINE IS RUNNING. As a product engineer for a company that makes alternators and starters, I am continually stunned by this troubleshooting technique. Many parts counter guys tell customers to do this stunt which is the best way known to blow a voltage regulator or damage an ECU or other electronic modules in the car. The battery in a car functions to smooth voltage fluctations and eliminate tranisent voltages. Disconnecting the battery can produce 100+ voltage transients that can blast anything electronic. The alternator may or may not be able to keep the engine running with the battery disconnected and it has nothing to do with the operating quality of the alternator.

Your alternator may not be functioning properly. But, having 12.7 volts on the battery with the key off or several minutes is an indication that the battery is at least close to a full charge. Normally, you should be able to rev the engine to 1,500 RPM and at least see the battery terminal voltage begin to rise toward regulator set point (14.1 to 14.3 volts) with the alternator at 70°F.
 

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Dick_Larimore said:
NEVER, REPEAT, NEVER REMOVE THE BATTERY FROM THE VEHICLE CIRCUIT WHILE THE ENGINE IS RUNNING. As a product engineer for a company that makes alternators and starters, I am continually stunned by this troubleshooting technique. Many parts counter guys tell customers to do this stunt which is the best way known to blow a voltage regulator or damage an ECU or other electronic modules in the car. The battery in a car functions to smooth voltage fluctations and eliminate tranisent voltages. Disconnecting the battery can produce 100+ voltage transients that can blast anything electronic. The alternator may or may not be able to keep the engine running with the battery disconnected and it has nothing to do with the operating quality of the alternator.

Your alternator may not be functioning properly. But, having 12.7 volts on the battery with the key off or several minutes is an indication that the battery is at least close to a full charge. Normally, you should be able to rev the engine to 1,500 RPM and at least see the battery terminal voltage begin to rise toward regulator set point (14.1 to 14.3 volts) with the alternator at 70°F.
I have to agree with Dick taking a battery lead off while the engine is running is the worst thing you can do to a vehicles chagrining system I have been selling parts for 20 years and have seen this done a number of times only to have a perfectly good regulator fried.
 
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