Battery reading 12.2v ( ScanGauge 2 ) reading
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That's on the low side of what I would call acceptable. Are you doing a lot of short trips? (where the alternator isn't running for very long to charge it up)
Take it to an auto parts store and have it tested for free.
Take it to an auto parts store and have it tested for free.
I've found that OBD readers often show a lower voltage than a real meter. I've seen meters show 12.6 volts when an OBD reader is showing 12.2. Check it with a real voltmeter and see what that says.
OBD readers read voltage at the ECU, not the battery voltage.
Originally Posted By: Ndx
Hey Guys,
My ScanGauge 2 shows battery at 12.2V battery its about 2.5 - 3year old.
with almost everything off... and with radio on and off same reading.
should I be getting new battery ?
It needs to be tested if you are concerned. Either with a Midtronics or a carbon pile load tester.
I would not trust voltage measured anywhere but at the battery with a quality DVM and after the surface charge is removed.
Voltage is my least favorite way to test a battery.
Hey Guys,
My ScanGauge 2 shows battery at 12.2V battery its about 2.5 - 3year old.
with almost everything off... and with radio on and off same reading.
should I be getting new battery ?
It needs to be tested if you are concerned. Either with a Midtronics or a carbon pile load tester.
I would not trust voltage measured anywhere but at the battery with a quality DVM and after the surface charge is removed.
Voltage is my least favorite way to test a battery.
load test your battery is the only way to properly determine the state of your battery health.
Getting a scangauge reading means nothing (due to lack of load).
Q.
Getting a scangauge reading means nothing (due to lack of load).
Q.
heres a graph that represents the relative life of battery depending on voltage.
i'd replace your battery unless the CCA on there is significantley bigger than needed. Cold weather may put enough voltage drop so that you wont be able to start your car.
i'd replace your battery unless the CCA on there is significantley bigger than needed. Cold weather may put enough voltage drop so that you wont be able to start your car.
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Originally Posted By: Ndx
thx guys that's very informative!
I will measure at the posts.
Do your self a favor and bring the vehicle to AAP or AZ and ask them to test it for free.
I would draw any conclusions from a no load voltage reading.
thx guys that's very informative!
I will measure at the posts.
Do your self a favor and bring the vehicle to AAP or AZ and ask them to test it for free.
I would draw any conclusions from a no load voltage reading.
Originally Posted By: Ndx
thx guys that's very informative!
I will measure at the posts.
That's what I'd do and wait half an hour after turning the engine off to get the most accurate reading.
I recently had my Bimmer in to CTC for the required e-test.
When I picked it up, I don't know what they did but it was dead.
I suspect they left the ignition on some how.
They gave me a jump start and suggested I needed a new battery without testing it.
It's an older battery and does slowly loose it's charge more than a new battery would. It needs to be put on a charger if I'm not regularly driving it as is often the case in the summer months.
I only replace a battery if it fails completely.
Ndx, 3 years isn't that old so I don't think you should need to replace it but if you do I'll take it off your hands instead; I don't think you're far from me. I have a used battery I can give you for the trade-in.
thx guys that's very informative!
I will measure at the posts.
That's what I'd do and wait half an hour after turning the engine off to get the most accurate reading.
I recently had my Bimmer in to CTC for the required e-test.
When I picked it up, I don't know what they did but it was dead.
I suspect they left the ignition on some how.
They gave me a jump start and suggested I needed a new battery without testing it.
It's an older battery and does slowly loose it's charge more than a new battery would. It needs to be put on a charger if I'm not regularly driving it as is often the case in the summer months.
I only replace a battery if it fails completely.
Ndx, 3 years isn't that old so I don't think you should need to replace it but if you do I'll take it off your hands instead; I don't think you're far from me. I have a used battery I can give you for the trade-in.
JHZR2
Staff member
What's the situation? Engine on? Key at the on position but engine not running?
With ecu operating via key at on position, but engine off, that's about right.
So we need specifics. Car usually has to be "on" in order to turn SG on.
With ecu operating via key at on position, but engine off, that's about right.
So we need specifics. Car usually has to be "on" in order to turn SG on.
Originally Posted By: rslifkin
I've found that OBD readers often show a lower voltage than a real meter. I've seen meters show 12.6 volts when an OBD reader is showing 12.2. Check it with a real voltmeter and see what that says.
My scanguage always reads mid 13's when my voltmeter shows a bit over 14v...running.
I've found that OBD readers often show a lower voltage than a real meter. I've seen meters show 12.6 volts when an OBD reader is showing 12.2. Check it with a real voltmeter and see what that says.
My scanguage always reads mid 13's when my voltmeter shows a bit over 14v...running.
Also, what car? Some newer cars have "smart" alternators that reduce voltage to 12.5 volts under certain conditions. With no loads on the alternator and a fully charged battery, a newer car just may dial back the alternator if it can. Anything to save 0.1 gallons/hour...
My ScanGauge underreads voltage by 0.4 volts. I posted about it in April 2013.
2006 GMC Sierra 4.3l, NV3500,G80 locker rear, Formula Shell Synthetic 5W30, Wix 51036, Dexcool.
1987 BMW
2006 GMC Sierra 4.3l, NV3500,G80 locker rear, Formula Shell Synthetic 5W30, Wix 51036, Dexcool.
1987 BMW
Originally Posted By: Voltmaster
heres a graph that represents the relative life of battery depending on voltage.
Your image is broken
[edit] Nevermind it worked on my 3rd reload..... may have been a blockage in the NSA wiretap server.
heres a graph that represents the relative life of battery depending on voltage.
Your image is broken
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