Expected. Batteries with low capacity can still produce a lot of current but at the expense of voltage sag. A nearly dead battery can provide 10 amps and not have much voltage sag when powering just the ignition and other ancillary demands. However, when also attempting to drive the starter motor, it may continue to spin albeit slower than normal, but the battery voltage may drop below the minimum needed to power the ignition or control electronics. The voltage regulators have a minimum input voltage in order to function and supply the electronics with power…
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Glad you got your TSX started & running again. I’m not keen on jump starting modern cars like yours, could possibly damage sensitive electronic parts in both your car & car providing jump. Suggest in future if battery needs a recharge to use a portable battery charger overnight at the 2 amp charge rate. Chargers like that go for around $50.
A properly charged battery will measure closer to 12.6 volts than 12.0 volts. You’ve already discovered one problem when cranking with an iffy battery. Another, doing that can cause an over-current condition in the starter motor, and burn the solenoid contacts, even the windings. A couple of months ago I was thinking of cranking up my truck to do an errand, but it had been sitting unused for several weeks. So decided to check the battery first. It measured 12.3 volts. I didn’t attempt to start it at that voltage. Charged it with battery charger to 12.6 volts first.
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Thanks everyone. So charging a car battery with a charger can help extend it’s life I guess? Is it worth charging say for example every oil change?
The state of charge of the battery is such where it can leave stranded without notice.
If the alternator in the vehicle can’t fully charge the battery, a battery charger won’t either.
Replace the battery.
Tester
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Why would a new battery become discharged? Does this vehicle sit unused for periods of time?
This has to be the first time anyone has asked if they should charge a battery at oil change time .
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Lead acid batteries last longest if they are kept charged. Under normal circumstances, there should be no need to periodically charge the battery as the act of driving will keep the battery charged. However, if you do lots of short trips and not much driving in between, the battery can run a deficit due to the high demand of starting and not much run time for the battery to recover. The other scenario is if the battery routinely sits unused for long periods. In those cases, it may be beneficial to apply an external charger to keep the battery fully charged. Otherwise, not needed.
Your battery is more than 5 years old. In some areas and operating conditions, that is an expected useful lifetime…
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That describes much of our use in winter. Short shopping bouts. Little highway time. Lights and heater fan on. Cold Minnesota weather. I put each car on an overnight charger once or twice most winters.
What I have gleaned from this extend thread:
Old battery, jumped, car started and runs fine.
Read this again:
“The state of charge of the battery is such where it can leave stranded without notice.
If the alternator in the vehicle can’t fully charge the battery, a battery charger won’t either.
Replace the battery.
Tester”
Unanswered questions:
How long did the car sit without being driven.
Whether or not use consists of short drives that do not allow the battery to be recharged.
New question:
Why spend $50 for a battery charger that might extend the life of an old battery by a few months, that might strand you at any time?
Why put a battery on a charger at the time of an oil change? Every six months or year, between changes and charging.
I highly recommend you immediately get a new battery.
If this car is used infrequently, get a battery maintainer, note they must be kept plugged in when the vehicle is not in use. They maintain the battery, not a true battery charger:
“ Unlike standard and trickle chargers, a battery maintainer can be attached to a battery indefinitely without any fear of overcharging. This makes them perfect for seasonal vehicles that will remain idle for longer periods of time. They’re also great for maintaining batteries during cold weather, which can drain your battery’s power. Using a battery maintainer will help offset this draining effect and protect your battery’s charge.”
Another option is a battery charger that switches to “float”, after the battery is fully charged. The “float” function is similar to a maintainer, but I would not trust that function if left on for an extended time.
Third, IMO least desirable is a trickle charger.
A bad battery is tough on an alternator, if that goes expect many $$$ to replace.
Me? Batteries are replace every 3-4 years, period. I do not want to be stranded and waiting for roadside assist to come.
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