Thank you! i will try that out tomorrow. I had the car at the Toyota dealer service place today to have the battery condition checked and they said it was fine. Do you think they use this procedure (the one at the link above)? I'd like to get a more robust battery, but i don't know who would install it. Would the dealer install a nonToyota part? I did some searching today simply for an independent Japanese or Toyota car mechanic, but i never did find one.
My 2006 Prius has a timeout on the accessory mode. It switches off after a period time. Haven't timed it but would guess around 1.5 hours. I assume this is to protect the 12v.
i see. makes sense. That's what i've done before too, though not that long, not more than a half hour, just at lunch, before i realized how dramatically the SOC indicator went down, within less than 5 minutes, it went down from the normal 5 or 6 bars to right above purple, or all the way into purple--in 3 or 4 minutes. I didn't realize (until today) that the SOC indicator is for the traction battery, not the one that runs all the stuff when i'm parked. So when i used to run it in ACC mode, like with my previous cars, engine off (or not ready), it never did the kind of weird radical behavior that it did yesterday, there was no sign of any problem other than a rapid going down of the bars. Maybe because the interior light was left on all night, night before last, that created a more vulnerable condition. The battery continues to start the car up well, no sluggishness or delay. I'm going to check the voltage tomorrow. Richard posted a link to detailed instructions for this above. If it tests low on voltage, if i understand right, this means get a new battery. thanks
To conserve your 12 volt battery, and I might be repeating what someone else has written, I haven't read the whole thread, life is too short. To save the 12 volt battery put the car in the 2 presses of the power button with foot off the brake mode and adjust your windows where you want them, now press the power button 2 more times with your foot off the brake so just the accessories like radio work, not the AC fan and inverter coolant pump. Now you can sit and eat to the sound of the radio without stressing your battery. If your battery is old or has been abused in the past it may have reduced capacity. The Prius has a small 12 volt battery however normal demands on the battery are also very small as it isn't called on to spin the engine over. Enjoy your lunch and enjoy your Prius.
I disagree with you Pat. The way to avoid stress on the 12v battery is to have the car in the READY mode.
A dealer probably uses diagnostic equipment and not that procedure. But sometimes a technician gets lazy and does not perform a proper load test, so the procedure can be a useful checkup. If the battery passes then it's OK and you dodged a bullet :_> and don't need a new battery. If the battery needs replacing the easy solution is to have a dealer replace it with another Toyota, and then be careful with that one. I would guess that a dealer would not want to fool with a non-Toyota part, and if they did they would charge you a lot for performing an unfamiliar installation. Installing a non-Toyota battery seems like either a do-it-yourself job or a job for an independent mechanic. You might print out the instructions from that website, show them to the independent and get an estimate.
I performed the battery check procedure. I did it when the car was cold, not driven since yesterday. The parking brake was on when i did it. I don't know if those things matter, seemingly not. The voltage shown at step 1 was 12.6. The healthy range is 12.4 to 12.8. At the second step, current load on battery, it showed 12.3-12.4, alternating. Above 12.0 is healthy. At step 3, with the battery charging, it showed 14.4. The healthy range is 13.6 to 14.4. So it's right at the upper borderline of that one. Should i worry? Anyway, at this time, YAY. Still not clear why the car showed all those odd alerts and flashing lights and beeping. I'm really glad to have knowledge of this procedure to check the battery in the future. I'll keep the print out of it in the car. I sure appreciate all the help here.
The car showed all of those warning lights because you were drawing power from the 12v battery with the car not in the READY mode. Therefore you were running the 12v battery down.
OK, thanks. So would you say that if i had done this test during that episode, while the lights were flashing, the voltage would've been lower? Under those conditions, when the lights were flashing and the 12V battery was strained, if i understand right, the battery can recover and go back to normal, that apparently happened, but it can be permanently damaged by doing this, running off the 12V battery not in ready mode--what happens? what is it that permanently ruins it? The battery on my Accord went dead, apparently completely?, when it hadn't been driven for at least a couple of weeks. The AAA came out and jumpered it and then it was idling. I drove it around for about 10 minutes, came back to the house, parked it on the street and it died as i was pulling it alongside the curb and wouldn't start back up. I thought that meant it was toast but the AAA guy came back and jumpered it again and told me that in order to reach a full charge, i would need to let it idle while running for 3 or 4 hours, which i did, and it now acts like a new battery. What does it take to kill a battery? Not putting water in the cells? But do people put water in Prius batteries?
Repeatedly draining a lead-acid battery damages the lead plates and can cause permanent changes in the chemistry. Running it down once may have reduced its total life by some fraction, but since you didn't drain it completely and it now tests normally all is well. Don't worry about it. Go, and sin no more :_>
I have to take mine in just got off the line and a new 12V battery is 138.00 and 25.00 to install which is good for a dealership will get it done next week closing on a home friday and then moving
Just back from Toyota 200.00 bucks for a 12V batt(mine was a bit over 10v) and a oilchange we will see if it is ok withen a week