Battery starting voltage
#1
Burning Brakes
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Battery starting voltage
What voltage should I read at the battery terminal when starting a 2010 coupe. I am reading 9.03 volts when starting some told me 9.6 volts or above was fine . I was also told 9 volts or above was fine. I did a load test on the battery and it tested good. Please advise.
#3
Le Mans Master
The scope revealed that the voltage was dropping into the mid-7s during cranking, and yet the car still started, every time.
I replaced the battery anyway, and with the new battery the car turned over a lot quicker. Incidentally, it also improved the smoothness of the clutch release, of all things, probably because the charging system wasn't loading down the engine as much.
I'd say you've got some time. Maybe install a new battery this winter, when the temperatures drop.
Last edited by torquetube; 04-18-2014 at 02:25 PM.
#4
Safety Car
should have
minimum 12.5 to 13.0 volts
#5
Burning Brakes
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No it should not read 12.5 to 13 when the starter is turning because it draws hundreds of amps from the battery. Thats the voltage when there is no load on the battery. If you do a load test with a battery tester you will see the voltage drop down.
#6
Safety Car
didnt say that
properly operating system not running or turning over should show 12.5 to 13.0 volts
#7
Burning Brakes
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Correct the battery voltage shows 12.61 volts with no load when I tested it. I wanted to know what the normal battery voltage is when the starter is turning its either above 9 volts or above 9.6 volts. If someone has the service manual it will state it in the manual.
#8
Le Mans Master
I do, and I don't think it specifies a minimum cranking voltage.
#9
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NCM Sinkhole Donor
When I was managing the Chrysler OE battery business the number was 10.5 volts.
Remember that you can have good voltage, but lack amps. I have seen batteries with 13.25 volts but very low CCAs for various reasons such high specific gravity or paste shedding.
Also 12.61 id only about 80% state of charge. I retired in November and left all that kind of info the trash.
Remember that you can have good voltage, but lack amps. I have seen batteries with 13.25 volts but very low CCAs for various reasons such high specific gravity or paste shedding.
Also 12.61 id only about 80% state of charge. I retired in November and left all that kind of info the trash.