Alternator Output Voltage
11-03-17, 12:06 PM
#16
Back when I had my 2010 Camry I basically replaced the battery every 2 years or so, but I drive 25-30K/yr and invariably my battery would also get some abuse here and there as well, including lots of sub 20F starts during the winter, etc.
-Mike
11-03-17, 01:27 PM
#17
I am not sure that it is correct that the charging voltage drops as under hood temperature rises. It is tied to the batteries charging needs. When you first start the car the battery voltage drops and when the alternator senses this it increases the charge voltage to provide a higher amperage charge to the battery. Once the battery voltage comes back up it then drops the charge voltage to deliver less amperage so as not to over charge the battery (that's a bad thing too). There may be some subtle changes to the voltage that are related to temperature but it's mostly due to charging needs. Remember that a higher differential voltage between the battery and alternator will provide more potential for a higher amperage charge. Once the voltages move closer together the potential decreases and unless the alternator runs at a higher voltage it cannot produce the same charge.
11-03-17, 05:43 PM
#18
Lexus Test Driver
I am not sure that it is correct that the charging voltage drops as under hood temperature rises. It is tied to the batteries charging needs. When you first start the car the battery voltage drops and when the alternator senses this it increases the charge voltage to provide a higher amperage charge to the battery. Once the battery voltage comes back up it then drops the charge voltage to deliver less amperage so as not to over charge the battery (that's a bad thing too). There may be some subtle changes to the voltage that are related to temperature but it's mostly due to charging needs. Remember that a higher differential voltage between the battery and alternator will provide more potential for a higher amperage charge. Once the voltages move closer together the potential decreases and unless the alternator runs at a higher voltage it cannot produce the same charge.
Last edited by bclexus; 11-04-17 at 07:24 AM.
05-21-22, 06:01 AM
#19
I think you will find that the alternator's output voltage varies with underhood or ambient temperature. As underhood or ambient temperatures increase the output voltage is reduced to 13.8 volts or less. During cold weather charging voltage can increase into the 15 volt range. Thus, depending on conditions a sound alternator will have an output charging voltage range anywhere from 13 volts to over 15 volts.
It sound like yours is working just fine...
It sound like yours is working just fine...
05-21-22, 06:05 AM
#20
it was probably still the factory original battery. So, my car being a 2013 model, the battery/Car we’re built in 2012. That means the battery was at least 5 years old when it quit. That’s plenty of life out of a standard battery.
Now I’ve got a AGM battery. It should last at least 10 years. I had one in my 96 Camry that went 12 years before it quit. I put another AGM in it, and that one is still going after 6 years.
Now I’ve got a AGM battery. It should last at least 10 years. I had one in my 96 Camry that went 12 years before it quit. I put another AGM in it, and that one is still going after 6 years.
Thread
Thread Starter
Forum
Replies
Last Post
topgun129
ES - 1st to 4th Gen (1990-2006)
11
08-03-13 10:02 AM