Needed a battery, possibly a drain?

Mikeb33

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Last weekend the 2016 Civic Touring wouldn't start. Battery dead. My voltmeter showed 5V. I bought an interstate and it measured 12.5V and installed it. Drove the car about 20 minutes to reset everything. Seemed fine. Now 2 days later and not having been driven since, I popped the hood and checked and it had 12.25V. I expected 12.6V or so. So put the meter in Amps mode and connected between the battery and cable. After the initial surge, it settled at 0.068A draw. I know there's going to be some draw, but how much is excessive?
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calonzo

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Last weekend the 2016 Civic Touring wouldn't start. Battery dead. My voltmeter showed 5V. I bought an interstate and it measured 12.5V and installed it. Drove the car about 20 minutes to reset everything. Seemed fine. Now 2 days later and not having been driven since, I popped the hood and checked and it had 12.25V. I expected 12.6V or so. So put the meter in Amps mode and connected between the battery and cable. After the initial surge, it settled at 0.068A draw. I know there's going to be some draw, but how much is excessive?
Searching google there are many different opinions. So, I will try to come up with a somewhat scientific answer.

I checked the specs on our battery group from one manufacturer and the "reserve capacity" was 45. This is how many Amp-Hours of energy the battery can survive without being charged and still be able to start the car. I believe the owners manual says you should start your car every 2 weeks to avoid a dead battery. 2 weeks is 14 days, multiplied by 24 hours is 336 hours. If you divide 45 Amp-Hours by 336 hours, you get 0.133 Amps.

So, given that, I would say 0.068 Amps on a good battery should last about 4 weeks before going dead.
 

blitz

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Last weekend the 2016 Civic Touring wouldn't start. Battery dead. My voltmeter showed 5V. I bought an interstate and it measured 12.5V and installed it. Drove the car about 20 minutes to reset everything. Seemed fine. Now 2 days later and not having been driven since, I popped the hood and checked and it had 12.25V. I expected 12.6V or so. So put the meter in Amps mode and connected between the battery and cable. After the initial surge, it settled at 0.068A draw. I know there's going to be some draw, but how much is excessive?
Have you installed any electronic accessories that may be drawing power while the car is powered Off?

Poor wiring during installation of electronics should be rechecked to ensure there is no resistance drawn from the wires (+) to the frame of the car.
 

Gruber

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Last weekend the 2016 Civic Touring wouldn't start. Battery dead. My voltmeter showed 5V. I bought an interstate and it measured 12.5V and installed it. Drove the car about 20 minutes to reset everything. Seemed fine. Now 2 days later and not having been driven since, I popped the hood and checked and it had 12.25V. I expected 12.6V or so. So put the meter in Amps mode and connected between the battery and cable. After the initial surge, it settled at 0.068A draw. I know there's going to be some draw, but how much is excessive?
As I said in some other recent battery thread, it's not so easy to measure the idle battery drain on a modern car. You have to wait some undefined length of time after you reconnect the battery through the amp meter to be sure it drops to the final reading. This real idle draw might be a bit smaller than what it shows immediately after connecting the battery.

If your battery indeed draws this current, the 51R would get totally discharged in about 3 weeks. It would not be able to start the car much earlier than that.

Searching google there are many different opinions. So, I will try to come up with a somewhat scientific answer.

I checked the specs on our battery group from one manufacturer and the "reserve capacity" was 45. This is how many Amp-Hours of energy the battery can survive without being charged and still be able to start the car. I believe the owners manual says you should start your car every 2 weeks to avoid a dead battery. 2 weeks is 14 days, multiplied by 24 hours is 336 hours. If you divide 45 Amp-Hours by 336 hours, you get 0.133 Amps.

So, given that, I would say 0.068 Amps on a good battery should last about 4 weeks before going dead.
I'm afraid you confused some things. First, the 45 number is not usually called "the reserve capacity" which is given in minutes. It's just the total battery capacity in Ah. After pulling out that 45 Ah, it will not start the car, it will be practically completely discharged.
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