Is running you rbattery dead bad for it?

[Shinare]

I've still got the stock battery in my 07 yaris but this last Thursday when removing my dash stuff to paint I turned on the map lights and accidentally left them on. Sunday when I needed to use my car to pick up my daughter I found it to be completely dead. Not a single anything had power, no dash lights or anything. I jumped it, drove about 20 minutes to pick her up. Turned off there to help load stuff. Cranked over just fine and drove back 20 minutes home. This morning it started just fine as well. Should I be worried that I somehow damaged my battery by running it dry or will it be fine?

[RedRide]

Yes it can be.
A standard lead acid battery that has been run dead can have its life shortened depending on its age/condition.

How much it will be shortened is open to debate.
If it was the first discharge and it was in good shape, it may fully recover with no noticable shortened life.

[severous01]

yes it's bad. unless it's a blue-top or deep cycle battery they're designed to semi-discharge and then be fully recharged. they should never get below about 11v, and they should always charge to at least 12.6v before you shut it down.

[why?]

yea, it will hurt the battery as was said, but how much? Can't really tell. Was it an easy jump?

[Shinare]

yea, it will hurt the battery as was said, but how much? Can't really tell. Was it an easy jump?

I just had my wife's Jeep in the garage next to me, ran the cables over and connected them up. I didn't start up the Jeep. When I cranked the Yaris it sounded like it was struggling to turn over, but after the initial turn over it started right up. I assumed the struggle to turn over was because the jeep was not running and poor contact with the jumper cable leads.

[nemelek]

My experience is yes. Maybe not right away, but I believe that it shortens up the life of a battery. I would put the car on a charger.

[why?]

I just had my wife's Jeep in the garage next to me, ran the cables over and connected them up. I didn't start up the Jeep. When I cranked the Yaris it sounded like it was struggling to turn over, but after the initial turn over it started right up. I assumed the struggle to turn over was because the jeep was not running and poor contact with the jumper cable leads.

i've never heard of being able to jump a car with another car that was off!!! wow.

i agree with grabbing a charger/desulfator thing, but just on general principles more than anything.

[MadMax]

It can be done, but it's not advisable! Doing so puts a strain on both vehicles' electrical systems, which Shinare experienced.

Next time start the Jeep up before jumping the Yaris (which, oddly enough, I have both of as well!).

Cheers! M2