Dead battery

[Mikeez]

Hey guys, I've not used my car for 1 week. The battery is dead. I will only use it for this sunday...

Should I disconnect the positive terminal of my battery?

[JohnJuan]

What are you hoping to accomplish by disconnecting it? I've left mine for a week before with no ill effects.

[swarb]

If it's dead, you better charge it before it stays dead. The longer you wait, the less chance it can be revived.

[stugray]

Disconnect it and recharge it while it is unhooked.

Jumping a car with a dead battery then letting the alternator charge it back up from dead is a sure fire way to kill a prefectly good alternator (assuming it was good to start with).

[TheVoiceOfReason]

Originally Posted by JohnJuan

What are you hoping to accomplish by disconnecting it? I've left mine for a week before with no ill effects.

If you have the smart key/push button ignition, there is a lot more draw on the battery while parked than without. Mine went dead after sitting for about 8 days a week ago. Charged up and started without issue fortunately. If you know you won't use the car for some time, disconnecting or using a battery tender is probably a good idea.

[Eski]

Originally Posted by TheVoiceOfReason

If you have the smart key/push button ignition, there is a lot more draw on the battery while parked than without. Mine went dead after sitting for about 8 days a week ago. Charged up and started without issue fortunately. If you know you won't use the car for some time, disconnecting or using a battery tender is probably a good idea.

shenanigans. there is not enough of a draw on the battery to drain it dead. there is no need to disconnect a battery for a small time like 8 days. maybe over a month, yes.

if your going to disconnect your battery like this^ then you should get a memory saver to plug in to save your settings, otherwise once you disconnect the neg cable you will reset all your settings to factory.

[rice_classic]

Or ditch the crappy battery that comes with the MT version of our cars and buy something with enough CCA's that you won't be left stranded. I ditched the crappy factory 390 CCA battery for a NAPA 640 CCA unit and life is much better.

Seriously.. A high compression engine and the stock batter is only 390 CCAs.. That's some BS right there. The AT version of our car I think got at least 500 CCAs (correct me if I'm wrong).

[finch1750]

Originally Posted by rice_classic

Or ditch the crappy battery that comes with the MT version of our cars and buy something with enough CCA's that you won't be left stranded. I ditched the crappy factory 390 CCA battery for a NAPA 640 CCA unit and life is much better.

Seriously.. A high compression engine and the stock batter is only 390 CCAs.. That's some BS right there. The AT version of our car I think got at least 500 CCAs (correct me if I'm wrong).

Not sure about that. From what I can tell my battery (Panasonic 55D23L) is only 390 or 400 CCA. Can someone with MT chime in on their battery number?

And fwiw my battery crapped out totally after about 30 months of daily driving.

[stevesnj]

Originally Posted by Mikeez

Hey guys, I've not used my car for 1 week. The battery is dead. I will only use it for this sunday...

Should I disconnect the positive terminal of my battery?

Just disconnect both cables and charge it with a 2 amp charger, a lower amp charging is better than like a 6 amp. Keep it on charge the whole week it wont harm anything, if any cell plates are sulfated they will desulfate with a charge for a week. Unless batteries are damaged they won't go bad, batteries go dead from sulfation. You can snap a battery back to life if you do like a week or 2 on a six amp charge topping with distilled water every once in a while. Also look for anything that may be staying on when the car is off. Something is draining the battery, on a new car I'd get a multimeter and make sure you are putting out 13+ volts at 2000 rpm consistently from the alternator with lights and a/c on for a load. No drops at a steady 2000 rpm and the alternator is good.

[Mikeez]

Thank you all for your inputs, just to let you know. Reason I disconnected it is due for the battery to not drain more power. I am not trying to accomplish anything, I will call Road Assistance to come jump start it. Since its nose in inside my garage.

How many time can I call scion road assistance (Canada) ?

[zc06_kisstherain]

Originally Posted by Mikeez

Thank you all for your inputs, just to let you know. Reason I disconnected it is due for the battery to not drain more power. I am not trying to accomplish anything, I will call Road Assistance to come jump start it. Since its nose in inside my garage.

How many time can I call scion road assistance (Canada) ?

or you can take out battery and charge it inside home.
i've done it because of same reason my car's nose is at corner.
I left my car for 2 weeks in below 20 degree and it went dead. bought battery charger and charged inside garage then started the car right back up after one day

[TheVoiceOfReason]

Originally Posted by Eski

shenanigans. there is not enough of a draw on the battery to drain it dead. there is no need to disconnect a battery for a small time like 8 days. maybe over a month, yes.

if your going to disconnect your battery like this^ then you should get a memory saver to plug in to save your settings, otherwise once you disconnect the neg cable you will reset all your settings to factory.

I agree that this usually wouldn't be the case, but this has been happening fairly often lately to people with the stock battery in the cold. There have been 4 similar threads in the last month.

http://www.ft86club.com/forums/searc...archid=8573373

I read in on of those threads that someone tested a new car on the lot and it was drawing 150mah while off (havent checked mine). From what ive found, the stock battery is 60ah. If these are both true, then the battery would go dead in just over 16 days in perfect conditions. The cold and the quality of the battery are both going decrease this time. This battery really doesnt seem to like the cold. For me it was getting below 0F while I was gone, never above freezing.

[stugray]

Originally Posted by TheVoiceOfReason

From what ive found, the stock battery is 60ah. If these are both true, then the battery would go dead in just over 16 days in perfect conditions. .

I agree. In fact a 60Ah battery discharging at .150A will reach 40% state of charge (60% depth of discharge) in 10 days.
At 40% SOC the voltage would only be 12 volts, and when you crank it would drop to below 11 volts.

My 2013 MT has the original battery and I find that I am low on charge if I make just a few short trips around town.
It seems that this car has a higher than average current draw under normal operating conditions than other cars.
Now I try to shut of all electrical systems before shutting the car off so that I have less load when I go to start it again.

[rice_classic]

Originally Posted by finch1750

Not sure about that. From what I can tell my battery (Panasonic 55D23L) is only 390 or 400 CCA. Can someone with MT chime in on their battery number?

And fwiw my battery crapped out totally after about 30 months of daily driving.

I'm 100% positively sure about the Panasonic battery is 390 CCA on the MT FRS. It said it right on the top of it.