battery gauge reading
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Joined: Dec 2008
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battery gauge reading
Hello what should the battery gauge reading be after car is at normal operating temp at idle. When i turn on lights or a/c the meter drops to about 12.3 and when i start driving goes back up to13.7 what could be issue Thanks
Team Owner
Joined: Jul 2006
Posts: 22,167
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From: Kannapolis NC
With no car information, no profile filled out, it's just a stab. Do you have an underdrive pulley? Is your belt slipping? Do you have loose/corroded connections on the battery or starter wires? Just general ideas, much like the question.
Tech Contributor
Joined: Dec 2006
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From: Van Buren Arkansas
Wounded Warrior Escort '11
It sort of depends on the electrical load at the time. Fan motors on, the voltage will be lower and so on. Best way to know is to insure its running at around 14.1 or so when you are driving down the road and the electrical load is a minimum. The static battery voltage measured with a meter when the ignition is off, should be above 12.5vdc. Usually for a newer battery, I think most see like 13.1 or so...again, ignition off.
Tech Contributor
Joined: Dec 2003
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
The DIC voltage reading gives alternator output. It will always measure an inaccurately low voltage on the battery when the car is off. Anything from 11.0-11.9 is normal in this mode. With the engine on, the voltmeter should show between 13V and 14.5V.
The actual reading as dgrant says will depend on battery state versus engine and electrical load. A cold car with a heavy load will be towards the higher end of the scale. At idle the alternator output will be lower and 12.3 is not unreasonable.
The actual reading as dgrant says will depend on battery state versus engine and electrical load. A cold car with a heavy load will be towards the higher end of the scale. At idle the alternator output will be lower and 12.3 is not unreasonable.
