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Old Mar 20, 2021 | 11:48 AM
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Default Voltage??

My 992 runs at about 12.9 my GT four was 14.8 running. 12.9 seems a little low but is it normal? Carl
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Old Mar 20, 2021 | 12:42 PM
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Are you measuring by the gauge or a Durametric readout?
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Old Mar 20, 2021 | 12:46 PM
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Originally Posted by Carlo_Carrera
Are you measuring by the gauge or a Durametric readout?
by the gauge driving. Carl
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Old Mar 20, 2021 | 12:49 PM
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Mine is a LiPo battery and reads 13.6 mostly.on average when driving. but will range from high 12s to 14.2. Lead Acid will be different.
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Old Mar 20, 2021 | 01:41 PM
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Originally Posted by 4carl
by the gauge driving. Carl
It has been my experience the gauges are not accurate and vary from car to car. 12.9 is low but I would plug in a Durametric to be sure.

How old is the battery?

Last edited by Carlo_Carrera; Mar 20, 2021 at 01:50 PM.
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Old Mar 20, 2021 | 02:40 PM
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Originally Posted by Richard_Wallace
Mine is a LiPo battery and reads 13.6 mostly.on average when driving. but will range from high 12s to 14.2. Lead Acid will be different.
My LiPo only ever reads 13.3-13.4. Doesn’t matter if it’s a 5 minute drive or a 1hr slog, never changes.
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Old Mar 20, 2021 | 05:51 PM
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Originally Posted by Carlo_Carrera
It has been my experience the gauges are not accurate and vary from car to car. 12.9 is low but I would plug in a Durametric to be sure.

How old is the battery?
new 992s ...carl
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Old Mar 20, 2021 | 06:04 PM
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My 992 with LiPo battery seems to read 13.4-13.6 on the car gage when driving. My 991 with lead acid battery reads 14.8-14-9 when driving. Same for my 2013 Cayenne GTS.
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Old Mar 20, 2021 | 07:24 PM
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Originally Posted by 4carl
new 992s ...carl
Take it to the dealer and have them plug in to a Durametric and see if the gauge is accurate and see if there is a fault somewhere in the charging system.
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Old Mar 20, 2021 | 08:39 PM
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https://www.porscheclubgb.com/forum/tm.aspx?m=1074688

apparently if the battery is fully charged the charging system will not put extra voltage in . It has something to do with fuel economy the alternator isn’t producing current there’s less drag. As a battery starts to drop the alternator will kick in. The reason why mine was showing less than 13 V is the battery was fully charged because I always leave the car plugged into a battery tender.carl
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Old Mar 20, 2021 | 08:43 PM
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Originally Posted by mathus7
My 991 with lead acid battery reads 14.8-14-9 when driving. Same for my 2013 Cayenne GTS.
This is normal.
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Old Mar 20, 2021 | 09:37 PM
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Originally Posted by 4carl
My 992 runs at about 12.9 my GT four was 14.8 running. 12.9 seems a little low but is it normal? Carl
My advice to you is stop staring at your voltage reading. It varies.

Lead/Acid resting voltage is 12.6~12.8v.

When you first fire up your car it will drag it down a little as your system turns and powers on.

Then when start the car, the alternator kicks in raising the voltage, at which time the voltage will vary from the high 12s to the mid 14s.

Don't worry about it, this is normal, and will fluctuate depending on ambient temp, A/C, lights, etc.


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Old Mar 20, 2021 | 09:39 PM
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Originally Posted by 4carl
https://www.porscheclubgb.com/forum/tm.aspx?m=1074688

apparently if the battery is fully charged the charging system will not put extra voltage in . It has something to do with fuel economy the alternator isn’t producing current there’s less drag. As a battery starts to drop the alternator will kick in. The reason why mine was showing less than 13 V is the battery was fully charged because I always leave the car plugged into a battery tender.carl
Exactly.

A person should be more concerned when your voltage reads high when driving (as this means either the battery is old, or not holding a charge).
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Old Mar 20, 2021 | 11:08 PM
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Originally Posted by 4carl
https://www.porscheclubgb.com/forum/tm.aspx?m=1074688

apparently if the battery is fully charged the charging system will not put extra voltage in . It has something to do with fuel economy the alternator isn’t producing current there’s less drag. As a battery starts to drop the alternator will kick in. The reason why mine was showing less than 13 V is the battery was fully charged because I always leave the car plugged into a battery tender.carl
It would have been helpful know at the very beginning that you leave the car in a charger constantly.
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