through avr
When the alternator on a vehicle is in the charging mode its output is close to 14.5 volts. If a bulb is rated at 12 volts, which is the voltage of a vehicle battery at rest, when the alternator comes on line at a higher voltage the life span of the bulb will be shortened.
When the alternator starts charging the battery voltage will increase about two volts to charge the battery.
the alternator voltage at the battery should be between 12.4voltsv-13.6 volts
13.5 to 15.5 volts.
The voltage for this is 12 volts The alternator/generator should be producing 13.5 to 14.5 volts
13.5 to 16 volts.
Automotive Alternator Output VoltagesWith a properly operating alternator, AND electrical system, a voltage output range of 13.5 Volts to 16 Volts is considered acceptable.Just the alternator puts out around 120 vac, but most newer alternators include a built in rectifier that limits voltage output to between 13.5 and 15.5 volts DC depending on speed.
Check the voltage at the battery with the engine running. It should read from 13.5 volts to 16 volts. If it reads lower than 13.5 volts the alternator is defective.
the voltage regulater is built into the alternator it regulates how much volts gives to the battery
The easiest way to check is apply a volt meter to the battery terminals. With the engine off the voltage should read around 12 volts. With the engine running there should be an increase in the voltage to around 14 volts. If the voltage reading stays at or decreases from the engine off level then the alternator is probably not working. I would then remove the alternator and take it to an auto parts store and have it bench tested to check it for proper operation.
The voltage should be in the range of 13.2 to 14 or so volts. It should not go over 15 volts.
In my 1993 Altima, I've had that problem 3 times. Each time, it was the alternator. I used a simple voltmeter check to isolate the problem. Battery voltage should be 12-13 volts without the engine running. When the engine is running, that voltage should increase to 14-16 volts. If the voltage does not increase, your alternator is bad...( NOT! the battery won;t go past 12.6 volts....they dont make them to go that high!}