Replace 12v battery?

Just had a look at an Optima yellow top in size 51. It looks like it will just fit, but the terminals are backwards and the wrong diameter. So some work would be needed to use it. Probably doable though.

 

<div class='quotetop'>QUOTE(lagreca @ Jul 17 2007, 01:08 AM) [snapback]480113[/snapback]</div>

If I were that worried, I'd carry one of those self-contained jump start units that Costco has for around $40, it might even store under the trunk floor. Even if you replaced the stock battery with a larger capacity one that would fit in roughly the same space it would probably only run 20% longer before running down... but it would still run down eventually. I run a 50-watt ham radio transmitter off of that little battery, and am not too worried about the battery draining. As long as you have the ready light on the dash, if it you drain the 12v too low it will get charged up again anyway. Remember the 12v battery does not need to provide that much amperage... it mostly just needs enough juice to boot the computer.

 

<div class='quotetop'>QUOTE(abq sfr @ Jul 18 2007, 11:27 AM) [snapback]481054[/snapback]</div>

Yep, I bought one from WalMart for $35. It is a Black and Decker brand, but it is actually made by Vector and is also sold under that brand (possibly even cheaper).

I think it would fit under the deck lid, but it would have to be layed down on its side; the instructions recommend keeping it upright. I store mine on the right side of the cargo area above the 12v battery. I have it bungie corded to the cargo tie down, so it won't become a projectile, and having it visible reminds me to check the charge level once a week or so.

Another advantage is that you can use it to jump other vehicles without involving your Prius.

 

If you're going to listen to the radio or use other accessories for a long time, just put the car into "ready" mode as if you're going to drive away. The traction battery will keep the 12v battery charged, and the ICE will start if it needs to charge the traction battery.

In most cases, the ICE will never need to start, because the traction battery will be able to keep the 12v system charged for a long time.

 

Just put your car into IGN-ON mode and you can run your radio about forever. The HV battery will discharge, but it will take a long time. Plus, the HV battery S.O.C. will be displayed on the MFD, so if it gets too low, either shutdown, or go to READY mode and let the ICE recharge it.

Don't think I'd sit around in READY mode unnecessarily, or unattended. Someone could bump the shifter and then the car could easily move.

 

<div class='quotetop'>QUOTE(9G-man @ Jul 18 2007, 09:01 PM) [snapback]481387[/snapback]</div>

They have to step on the brake pedal and bump the shift lever at the same time. Otherwise it will just beep.

 

Press the brake pedal, move the shifter, and release the parking brake.

Not something that would happen accidentally: there are three separate actions, requiring two feet and one hand.

 

Does anyone recall "Unintended Acceleration". It almost put Audi out of business in the early '80's. And it required 4 seperate actions. The three you mentioned and 1 more......Stupidity.

The main point here is IGN-ON mode will accomplish what READY mode will for extended radio listening without potential for problems. And it eliminates one unnecessary ICE start cycle. The first one.

 

Point taken on using IGN-ON to avoid ICE operation altogether.

 

<div class='quotetop'>QUOTE(9G-man @ Jul 18 2007, 11:01 PM) [snapback]481387[/snapback]</div>

IGN-ON will not allow the ICE to come on to recharge the hybrid battery. If you don't pay attention to the SOC you can run it down too far and have a problem that only the dealer can fix.

Leave the cart in Ready. Bumping the shifter will do nothing without your foot firmly on the brake.

Wayne

 

<div class='quotetop'>QUOTE(9G-man @ Jul 19 2007, 12:01 AM) [snapback]481387[/snapback]</div>

<div class='quotetop'>QUOTE(FireEngineer @ Jul 19 2007, 02:38 PM) [snapback]481726[/snapback]</div>

Isn't that what I said?

 

So for a 2-hour drive-in movie, IG-ON for the FM Radio signal movie soundtrack, no problem? I have been wondering about that.

 

If you don't go into "ready" the car will not start the ICE to charge the traction battery. So eventually it will shut off. It will not allow you to fully discharge the traction battery. Even if you try desperately to do so. Not related, but do keep in mind, the car WILL allow you to fully discharge the 12V battery, so be careful with that.

If you go to "ready", it will run the ICE only when the SOC gets "too low". Note that in my limited experience, the ICE consumes about 1.2 L/hr in this state when it's running. It seems to run for 30 sec to a minute every 10 min or so (depending on what you have turned on). So I don't think you'd burn much fuel during a 2-3 hr movie. But it will impact your mileage, if you care about that.

 

Experiencing low gas mileage after new iridium spark plugs installed, deals says the situation will self correct in a few weeks.

True??

 

Probably. The dealer may have left it ON for a while.

 

Back then shift locks were rare. All you needed to do was move the gearshift out of Park.

But the problem with the Audi was with people hitting the (poorly positioned) accelerator pedal when they meant to hit the brake.

[ame="http://en.wikipedia.org/wiki/Audi_5000"]Audi 100 - Wikipedia, the free encyclopedia[/ame]

 

Go to ACC, NOT IG-ON.
If you do IG-ON you'll be using a lot more 12V power you don't need and no recharging.

It *should* be fine for a 2hr movie, but it's possible it might not be if your 12V battery is particularly old/weak. Best bet would be to go into ready maybe partway through for a bit, or just keep a 12V jump-pack with you just in case.

Levi

 

Argh... I hadn't thought about drive-ins. The Canadian prius has the DRLs on always in ready mode.... not likely to make you any friends at the drive-in