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Honda battery or system problem

2012 Honda Accord ~ 47k miles not used everyday.
I had a problem a couple of weeks ago with the car not having enough juice to turn over. I used a lead acid jump pack to start it and took it to Advance Auto Parts where I had purchased their AutoCraft Gold Battery, Group Size 35, 640 CCA less than 2 years ago. They where getting a new battery for me when I mentioned the old one was still under a free replacement warranty. Then they insisted on testing the old battery, which they said was good! and then the charging system which they said was good! Now I have the problem again. With the battery pack seemingly near full charge I have trouble getting the car to turn over. It eventually started with the pack. On my return from a short trip from the store I had the same situation. Now the question I THINK I need an answer to is this: Can a bad battery draw so much current from a ‘good’ battery pack that the car would have trouble turning over? And if so how could the battery test good and how to prove it has a problem to the store personnel. :confused:

I’d get it checked somewhere else, they may be trying to avoid giving you the free replacement battery.

“Can a bad battery draw so much current from a ‘good’ battery pack that the car would have trouble turning over?” yes. The battery packs have limited capability, less than your car battery. And a dead battery cannot be raised to the point where you can start the car.

Borrow a voltmeter, or buy one that plugs into your cig lighter socket, for about $8 ( and measure the battery voltage, that will give you an idea of it’s condition. It should read 12.6 volts.

Another possibility is corroded and/or loose cables. You can unbolt them (be careful) and check the connections for corrosion. Check both ends. That can also explain why the battery pack won’t start the car, the current still has to go thru the same cables.

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12.2 V after a half hour idle probably not enough to bring up a drained battery. I have a clamp on Ammeter and I am thinking I could see what the current draw is while starting or rather not starting. The battery terminals look good. Negative to body looks good. The Positive goes to alternator ? Probably in the bowels of the car, maybe tomorrow when things have cooled down.
BTW can a car run with the positive battery disconnected and started w/ a jump pack?


Don’t do that unless you want to fry some very costly electronics. Just because the battery connections look good does not mean they are.

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The heavy positive cable goes to the starter.

there could well be corrosion inside the connection. You have to take each off and inspect the mating surfaces.

If you have a voltmeter you can measure the voltage from each of the two terminals on the starter to the starter case. When you attempt to start, they both should be about 10 volts or higher. Lower indicates bad cables or bad battery. above 10 volts and the starter should crank if it is OK.

I was afraid someone would be saying that :grinning::money_mouth_face::frowning_face:

That I can do.
Just to get this in my head, is there a situation where a ‘working’ alternator would fail to charge a good battery with good connections?
If I have to be a bit forceful at the store I want to know what I am talking about. Knowledge IS Power !! :face_with_raised_eyebrow::books:

Be sure to do this safely. I’d disconnect the negative terminal of the battery first, and leave it disconnected as you disconnect the others, check/clean them, and put the negative terminal connection back last.

I remember being told that 1/2 century ago.

The alternator is controlled by the regulator, or in most newer cars, by the engine computer. They check the battery voltage and control the alternator output to maintain it at full charge. The regulator, if there is one, is a separate small box bolted to the alternator or is part of the alternator. The computer is a separate box, and in the unlikely event it is bad, could tell the alternator to not charge the battery, or to overcharge it.

I am liking the word unlikely at this point, I was gonna take a leap and say a loose feed back connection to the regulator or computer would not result in an undercharge condition but then could be a fail safe that prevent an over charge, would not that invoke an error code?
I see there is still a no charge indicator on this car.

Why not just find a shop and pay the diagnostic fee and find out what is really wrong. Most shops if they get to do the work will waive that fee.

pay :open_mouth::grimacing::hear_no_evil: :laughing:

My Honda/Acura battery on my 2012 only lasted three years. I bought a NAPA battery after the tow truck started me. Are you sure you still have a free replacement? Sure they are guaranteed for 84 months but pro-rated, not free replacement. Just get a new battery.

New replacement, not prorated!
I am troubleshooting a bit this morning with some of the advice hear and from other sources. I am wondering how well the AAP tester works, it seemed to be fairly automatic. I am wondering what the current draw on a non navigation equipped Honda parked and with switch off might be expected to be.
Thanks again for everyone’s advice.

Everything turned off? The current starts out a bit high, perhaps 1 amp, perhaps several amps, at a guess. As the various computers go into sleep mode, that will drop, down to less than 50 mA probably. (0.05 amp)

Note that doing anything to the car will bring it out of sleep mode, such as opening a door.

Yup, tape down the door switches to allow parasitic draw testing without waking the car up.

Yesterday afternoon the battery was 12.2 V this morning it read 11.8 but started the car. The idle voltage was 14.22 with only the door open. With AC on it was 14.02.
My clamp on ammeter only goes down to 6 amps and seems to read about 1/2 amp at idle in the above situation. I have read some estimates to recharge a low battery in place that go as low as 3 seconds for a good battery. This is assuming 30 or more Amps going into the battery, I am doubting this assumption.
I am taking a ride and am parking near a Walmart, so worse case I may be able to buy one of there batteries. Lunch is by the Advance Auto Parts :neutral_face:

I don’t understand what you are writing but it takes 2 to 3 hours to recharge a good battery with a battery charger. If the battery was discharged over a long period of time (vehicle in storage) it can take 8 to 12 hours with a battery charger.

It can take longer to recharge a battery with the vehicles charging system due to the lower voltage compared to a battery charger.

Like I said, replace the battery. The resting voltage is too low and the charging voltage is OK. I don’t think you are going to get a free battery though.