Woke up to dead battery. Trying to figure out why.

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I have a 2008 Suburban with a new AC Delco battery installed just a few months ago. 10 days ago, the ignition got left on while a family member ejected a DVD from the player. It stayed on all night and the battery was dead the next morning. I tried jumping it with my wife's car. I got dash lights to come on but it still wouldn't turn over. So, I trickle charged the battery for about 8 hours, then drove it for an hour once it started. The battery then performed great all last week.

Then yesterday, I ran several errands and everything seemed fine. I was in the vehicle last night at 10:30 to grab some stuff before bed and lock it up. The key fob unlocked the door and the dome light came on just fine. But this morning at 7:30, it was dead as can be. All door locks, lights, etc were completely dead. Hooked up the wife's car to jump it and never even got a light to come on.

Once the bus drops me off and I get home tonight, I plan to take it to a parts store to have it tested. If it tests bad, it seems like an easy fix (new battery, knock on wood). If it tests fine, what could be going on?
 
You could have damaged the battery running it down. It seems that once you kill them to being totally flat its a [censored] shoot what they do after. Some come back to life like nothing happened and some just can't take it.

I'd put it on a good charger for awhile and see what happens. No harm taking it to get tested either. Does yours have caps to add water or is it sealed?
 
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If the battery tests good and we know the tester is good, then you have a parasitic drain and or bad alternator. Battery testers can be suspect though. Do you have a meter?
 
I had an Onstar module fail on a 2010 Equinox and drain the battery. Just pulled the CIM fuse. The module had already quit working several months before and then suddenly started draining the battery.
 
I've been meaning to look up how to disable OnStar in our Malibu. The position of the button on the rear view leads to it being hit accidentally when adjusting the mirror.
 
A solution to this problem on GM cars is an auto battery disconnect module which doesn't let the battery get down to discharge. Apparently GM has had a problem with computers which show an increased parasitic draw with time.
 
Originally Posted By: pcoxe
I had an Onstar module fail on a 2010 Equinox and drain the battery. Just pulled the CIM fuse. The module had already quit working several months before and then suddenly started draining the battery.


Same thing happened on my '08 Trailblazer. Onstar is a piece of c**p. It can also foul up the data bus and give you all kinds of weird indications and spook error codes.
 
A battery big enought for a Suburban, is likely 85 Amp hours capacity.

A trickle charger is generally 2 amps

A deader than doornail battery can be considered 100% discharged

2 amp( trickle charge) for 8 hours would return a small fraction of the charge back into the battery.

I wish people would stop thinking a trickle charge is magically restoratice, especiually if it is not left on for 24 to 48 or more hours.

Driving for an hour.

Well how much the laternator returns in this hour is Very variable, and the main variable is the voltage allowed by the voltage regulator.

If the battery was brought to and held at 14.5 volts for that hour, the battery might have gotten to 80 to 85% charged, and 85% to 100% charged, if continued to be held at 14.5v would require no less than 3.5 more hours.

But it is far more likley 14.X volts was allowed for aonly a few minutes before dropping to 13.7 ish volts.

So what has happened is the starting battery was drained, likley below 10.5v, which is considered 100% discharged on a 12v battery.

8 hours of trickle charge returned a very small portion of the charge to the battery, then the hour long drive might have also accomplished very little.

So the gasping and drowning battery was given barely enough to keep its head above the water line, and the unknown level of parasitic draw acted to submerge the battery again.

The Alternator is not a magical physics defying instant battery charger
A trickle charger applied for only a few hours is an insult to a deeply discharged battery that is big enough to crank a v8 engine.

Charge the battery fully. This might take 36 and likely more hours on your despicable 'trickle' charger. Investigate the vehicle's parasitic draw.

If the battery doe test bad, you likely killed it, or at least significantly contributed to its very premature demise.

A lead acid battery ideally wants to ALWAYS be at 100% state of charge. Hovering lower than this is detrimental. how detrimental is determined by how low it goes, and how long it remains there.

And a battery so Depleted it needed a Jumpstart, CANNOT be charged to true full 100% in less than 6.5 hours, and that is when the high amp charging source seeks and hold voltages in the mid 14's for that 6.5 hours.

Lesser voltages GREATly increase the charge times, no matter how powerful, amperage wise. the charging source is capable of. Voltage is electrical pressure. With not enough pressure there is little flow.
 
Sometimes cars freak out a little when the battery is run down and brought back without actually getting disconnected. Ive had good luck disconnecting the negative and recharging the battery that way, then hooking things back up and clearing all faults. Ive had a few BMWs, mostly 6 and 7 series, that had crazy fault codes that would not clear in a few modules unless we did a "battery reset"
 
We've had 2 issues with our GM charging system. First, an RKE/starter module had been exposed to water and corrosion ensued, causing a resistive load (of corrosion) between a batt and gnd terminal, thus slowly discharging the battery.

Second, a few weeks later, it was the alternator signal wire (orange PWM duty signal) from the ECM losing connection at the terminal due to contact resistance, causing the alternator to stand idly by as we drove and depleted the battery. Cleaned the terminal and reset it, installed a small DVM readout in the dash and now the alternator whistles away normally and all is well. Can't imagine how many alternators have been changed on these vehicles if the issue was a simple bad contact.
 
Wrcsixeight is right. You never fully charged the battery.

A trickle charger is not designed to restore a dead battery, but instead to maintain a fully charged battery. The 8 hour charge may have been just barely enough charge to get you going again, and the car's alternator was only just keeping things on even keel for a few days. How long were your drives between the first incident and the second? Any 3 hour or longer drives? If not, it's very unlikely that you ever got the battery anywhere near a full charge. If your drives were short, it probably never made it to even 50% charge.

If you haven't damaged the battery from totally draining it twice now, put it on a real charger, preferably a smart charger that can detect the condition of the battery, properly charge it, and tell you when you have a fully charged battery.

One like this.

https://www.amazon.com/SOLAR-PL2520-Pro-Logix-Battery-Charger/dp/B007P7ABE6/ref=sr_1_2?ie=UTF8&qid=1490667739&sr=8-2&keywords=clore%2Bsolar%2Bbattery%2Bcharger%2B12%2Bv&th=1


Or one of it's big brothers.

https://www.amazon.com/SOLAR-PL2520-Pro-Logix-Battery-Charger/dp/B007ESQW08/ref=sr_1_2?ie=UTF8&qid=1490667739&sr=8-2&keywords=clore%2Bsolar%2Bbattery%2Bcharger%2B12%2Bv&th=1

This one is the one in my garage.
https://www.amazon.com/SOLAR-PL2520-Pro-Logix-Battery-Charger/dp/B007ESQW08/ref=sr_1_2?ie=UTF8&qid=1490667739&sr=8-2&keywords=clore%2Bsolar%2Bbattery%2Bcharger%2B12%2Bv&th=1

https://www.amazon.com/SOLAR-PL2520-Pro-Logix-Battery-Charger/dp/B007ESQW08/ref=sr_1_2?ie=UTF8&qid=1490667739&sr=8-2&keywords=clore%2Bsolar%2Bbattery%2Bcharger%2B12%2Bv&th=1
 
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Thanks for all the well thought out, deliberate, sound advice. I appreciate folks weighing in.

The issue, though, ended up being very simple: one of the kids moved the DVD player from the AUTO to the ON setting, which means the key being off didn't turn it off. I knew it because as soon as I got the battery back in tonight (in the dark), I could see a bright, white light shining from the back seat ceiling. It was the two side lights on the DVD player.

Easier fix than I thought, but no matter how easy, the battery has been completely drained twice in less than two weeks. At this rate, she won't last long.

I did have a good experience at AutoZone tonight. They tested, charged and re-tested my batter over a 2 hr. period and wouldn't take a dime for it. When My family and I finish off the battery in the next week or so, I'll just go there to buy a new one.
 
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Is that aftermarket installation of the DVD player? Most OEM shut down everything when you take the key out. Some are even smarter and put them (e.g. interior lighting) on a timer and thus you might have them running for few minutes until they kill it.
 
Originally Posted By: wrcsixeight
A battery big enought for a Suburban, is likely 85 Amp hours capacity.

A trickle charger is generally 2 amps

A deader than doornail battery can be considered 100% discharged

2 amp( trickle charge) for 8 hours would return a small fraction of the charge back into the battery.

I wish people would stop thinking a trickle charge is magically restoratice, especiually if it is not left on for 24 to 48 or more hours.

Driving for an hour.

Well how much the laternator returns in this hour is Very variable, and the main variable is the voltage allowed by the voltage regulator.

If the battery was brought to and held at 14.5 volts for that hour, the battery might have gotten to 80 to 85% charged, and 85% to 100% charged, if continued to be held at 14.5v would require no less than 3.5 more hours.

But it is far more likley 14.X volts was allowed for aonly a few minutes before dropping to 13.7 ish volts.

So what has happened is the starting battery was drained, likley below 10.5v, which is considered 100% discharged on a 12v battery.

8 hours of trickle charge returned a very small portion of the charge to the battery, then the hour long drive might have also accomplished very little.

So the gasping and drowning battery was given barely enough to keep its head above the water line, and the unknown level of parasitic draw acted to submerge the battery again.

The Alternator is not a magical physics defying instant battery charger
A trickle charger applied for only a few hours is an insult to a deeply discharged battery that is big enough to crank a v8 engine.

Charge the battery fully. This might take 36 and likely more hours on your despicable 'trickle' charger. Investigate the vehicle's parasitic draw.

If the battery doe test bad, you likely killed it, or at least significantly contributed to its very premature demise.

A lead acid battery ideally wants to ALWAYS be at 100% state of charge. Hovering lower than this is detrimental. how detrimental is determined by how low it goes, and how long it remains there.

And a battery so Depleted it needed a Jumpstart, CANNOT be charged to true full 100% in less than 6.5 hours, and that is when the high amp charging source seeks and hold voltages in the mid 14's for that 6.5 hours.

Lesser voltages GREATly increase the charge times, no matter how powerful, amperage wise. the charging source is capable of. Voltage is electrical pressure. With not enough pressure there is little flow.
Originally Posted By: wrcsixeight
A battery big enought for a Suburban, is likely 85 Amp hours capacity.

A trickle charger is generally 2 amps

A deader than doornail battery can be considered 100% discharged

2 amp( trickle charge) for 8 hours would return a small fraction of the charge back into the battery.

I wish people would stop thinking a trickle charge is magically restoratice, especiually if it is not left on for 24 to 48 or more hours.

Driving for an hour.

Well how much the laternator returns in this hour is Very variable, and the main variable is the voltage allowed by the voltage regulator.

If the battery was brought to and held at 14.5 volts for that hour, the battery might have gotten to 80 to 85% charged, and 85% to 100% charged, if continued to be held at 14.5v would require no less than 3.5 more hours.

But it is far more likley 14.X volts was allowed for aonly a few minutes before dropping to 13.7 ish volts.

So what has happened is the starting battery was drained, likley below 10.5v, which is considered 100% discharged on a 12v battery.

8 hours of trickle charge returned a very small portion of the charge to the battery, then the hour long drive might have also accomplished very little.

So the gasping and drowning battery was given barely enough to keep its head above the water line, and the unknown level of parasitic draw acted to submerge the battery again.

The Alternator is not a magical physics defying instant battery charger
A trickle charger applied for only a few hours is an insult to a deeply discharged battery that is big enough to crank a v8 engine.

Charge the battery fully. This might take 36 and likely more hours on your despicable 'trickle' charger. Investigate the vehicle's parasitic draw.

If the battery doe test bad, you likely killed it, or at least significantly contributed to its very premature demise.

A lead acid battery ideally wants to ALWAYS be at 100% state of charge. Hovering lower than this is detrimental. how detrimental is determined by how low it goes, and how long it remains there.

And a battery so Depleted it needed a Jumpstart, CANNOT be charged to true full 100% in less than 6.5 hours, and that is when the high amp charging source seeks and hold voltages in the mid 14's for that 6.5 hours.

Lesser voltages GREATly increase the charge times, no matter how powerful, amperage wise. the charging source is capable of. Voltage is electrical pressure. With not enough pressure there is little flow.
Originally Posted By: wrcsixeight
A battery big enought for a Suburban, is likely 85 Amp hours capacity.

A trickle charger is generally 2 amps

A deader than doornail battery can be considered 100% discharged

2 amp( trickle charge) for 8 hours would return a small fraction of the charge back into the battery.

I wish people would stop thinking a trickle charge is magically restoratice, especiually if it is not left on for 24 to 48 or more hours.

Driving for an hour.

Well how much the laternator returns in this hour is Very variable, and the main variable is the voltage allowed by the voltage regulator.

If the battery was brought to and held at 14.5 volts for that hour, the battery might have gotten to 80 to 85% charged, and 85% to 100% charged, if continued to be held at 14.5v would require no less than 3.5 more hours.

But it is far more likley 14.X volts was allowed for aonly a few minutes before dropping to 13.7 ish volts.

So what has happened is the starting battery was drained, likley below 10.5v, which is considered 100% discharged on a 12v battery.

8 hours of trickle charge returned a very small portion of the charge to the battery, then the hour long drive might have also accomplished very little.

So the gasping and drowning battery was given barely enough to keep its head above the water line, and the unknown level of parasitic draw acted to submerge the battery again.

The Alternator is not a magical physics defying instant battery charger
A trickle charger applied for only a few hours is an insult to a deeply discharged battery that is big enough to crank a v8 engine.

Charge the battery fully. This might take 36 and likely more hours on your despicable 'trickle' charger. Investigate the vehicle's parasitic draw.

If the battery doe test bad, you likely killed it, or at least significantly contributed to its very premature demise.

A lead acid battery ideally wants to ALWAYS be at 100% state of charge. Hovering lower than this is detrimental. how detrimental is determined by how low it goes, and how long it remains there.

And a battery so Depleted it needed a Jumpstart, CANNOT be charged to true full 100% in less than 6.5 hours, and that is when the high amp charging source seeks and hold voltages in the mid 14's for that 6.5 hours.

Lesser voltages GREATly increase the charge times, no matter how powerful, amperage wise. the charging source is capable of. Voltage is electrical pressure. With not enough pressure there is little flow.


Great info here. You never fully recharged your battery.
 
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