Got a couple questions? How long will it take to recharge dead battery by just driving it? Can I just crank it and leave it setting in carport without driving it if ready is displayed, not turning off switch , leaving it on, just let it sit, will that also charge up the battery? Need help with answer fast. I did jump start this morning, not problem at all, must have left interior lights on.
The charging system in a Prius is very slow. It is charging whenever the car is in "Ready" mode. It is important to fully charge it as any lead acid battery is damaged by leaving it in an uncharged state. You need to attach a charger that is limited to about 2 amps for almost a full day to fully charge your 12v battery. JeffD
I left it on carport for about 20 min, that drained the big battery, then drove car and charged battery back up, let it sit again for 30 min. This time it only used 2 bars of battery. So I'm thinking it should be ok to drive on a 6 hour trip I got to make today, hope so anyhow. I need to purchase a jump and start, wife leaves inside lights on all the time, but this was the first time it actually killed battery. Any recommendations for a jump and start?
I have small Black & Decker that also is an air pump. Came in handy several times to inflate slow leaks. I've never had to jump my 2004 Prius (231k miles), but have jumped others many times. Just remember to keep the "Jump&Start" fully charged. Your 12v battery can't deal with discharges as it is not a deep discharge battery. I replaced mine at 8 years with an Optima yellow top which is designed to handle the use you wife puts it through. JeffD
Short answer: "just driving it" may never recharge it, ie: restore it more-or-less to 100%. With a decent charger, one or two overnight sessions should recharge it, if it's not too far gone. Look for an "intelligent" charger that charges in stages and tapers off to trickle charge, and gives you feedback as to the battery state. I'm using a CTEK 3300, but there are lots of choices.
That is not accurate ... charging current should be around 4A max 4.3 (short time maybe 5A) but make sure the charger is a smart one leaving 4-4.3 on too long could also damage your 12V battery...
Confused if you have a 6 hours drive you do NOT need to pre-charge your 12 V battery car will keep charging it and 6 hours is plenty unless the battery is really damaged .. in which case nothing but replacing will work anyway...
If you have a battery charger you can connect it to the terminals in the fuse box and jump start the car you would need something more then 2-4 A but a 10A setting will be most likely enough ... (DO NOT leave a 10A charger connected. Use it ONLY for the start ...) Then the car will be fine (unless you shut it off before 12V battery recharged sufficiently)
This is what I did, just drove it, 3 days now without any problems. It may not have a full charge on it but it keeps going so not going to be too concerned unless it happens again.
I just had an old craftman plug in 110 outlet charger, found the terminal in fuse panel and jumped it like I would any other car. I just used the lowest setting on charger, cranked up and been going 3 days now.
Make sure you did not leave any interior lights turn on; check the back trunk, it will drain the battery.
I don't know what was left on but will be prepared next time it happens with one of these. It will store easily in bottom back hatch area, only 4 inches thick. Got it for $67, I bought the Stanley with air pump built into it for other vehicle. You never know when you might need it of help someone else. Wal Mart had to best deal on Stanley,, Amazon had the best deal on Black in Decker. Get the Stanley 500-Amp Jump Starter at Walmart.com. Save money. Live better. Black & Decker JUS500B 500 Amp Jump Starter : Amazon.com : Automotive
