Battery Voltage

[stephen.robins]

Can anyone advise on what the battery voltage should be when the car is cold and at this time of the year? My car is garaged but if left for a few days the voltage only reads 11.9V. I would expect it to be over 12V. It always starts and the stop/start appears to work fine which I think is a sign of a healthy battery.
The car is only 3 years old and had a new battery installed before I purchased the car. I'm just a little paranoid that I may have a drain?

 

[Billybod]

A drain? There will always be a low current draw to keep your car “alive” to respond to key fob unlocking, alarm and monitoring etc. I think the owner’s manual advises to not leave uncharged (by driving or charger) for more than a month.
Regards
Bill

 

[Motorhead]

Hi Stephen,

11.9V with the engine off sounds a bit low. You should be looking at something like 12.6V - 12.8V for a fully-charged battery, although it’ll still be serviceable at around 12.4V - 12.5V.

You don’t mention how you’re measuring the voltage, but you would best measuring it with a multimeter rather than relying upon the onboard voltmeter.

If you can I’d always advise you to use a battery conditioner if the car’s not in daily use, especially at this time of the year with temperatures falling.

Jeff

 

[stephen.robins]

Hi Stephen,

11.9V with the engine off sounds a bit low. You should be looking at something like 12.6V - 12.8V for a fully-charged battery, although it’ll still be serviceable at around 12.4V - 12.5V.

You don’t mention how you’re measuring the voltage, but you would best measuring it with a multimeter rather than relying upon the onboard voltmeter.

If you can I’d always advise you to use a battery conditioner if the car’s not in daily use, especially at this time of the year with temperatures falling.

Jeff

Jeff,
Thanks for your reply. I'm taking the voltage reading from the dashboard. By comparison, my 981S never shows less than 12V before starting.
I have connected my battery conditioner this morning and it has been on for a few hours and is still not showing fully charged so it looks like the voltage was low.
Steve

 

[Scrounger]

Dan

 

[stephen.robins]

View attachment 8979
Dan

Dan,
Thanks as that is helpful. It took all day yesterday but my battery conditioner is now showing a full charge so it will be interesting to see the voltage before starting.
Steve