Battery issue...stumped!

Is this the 12V battery you're having problems with? I would guess so, since the lights run off the 12V battery. Have you ever replaced the 12V battery? Your "newer" battery could still be a few years old in a 2001.

Welcome to PriusChat, I'm sorry you're having problems. We'll try to help.

 

I do not believe that your Toyota shop is being helpful. Some other shop can test the battery to see if it has lost its original capacity. Visually inspect the battery connections for corrosion. They can also see if there is a high current drain when the car is off, which may or may not be due to your aftermarket electronics.

There have been previous discussions here on 12 volt battery replacement options, in case you need one. I suspect that you might.

As you are in the Bay area I will (once again) make a plug for Art's Automotive in Berkeley. If you can get that far

 

<div class='quotetop'>QUOTE(musician @ Jul 25 2007, 11:59 AM) [snapback]484698[/snapback]</div>

Navigation shouldn't be a problem, unless it stays on when the Prius is turned off. Check the wiring.

A new 12 v battery is not a huge investment, so if you continue to have problems, get rid of the old one. You may want to check the 12 v charging system.

Tom

 

<div class='quotetop'>QUOTE(musician @ Jul 25 2007, 10:59 AM) [snapback]484698[/snapback]</div>

3 things come to mind:

1) Something is draining the 12V battery while the car is off (Incorrectly installed navigation system?)

2) The battery is faulty and doesn't hold a charge.

3) The charging system is failing to charge the battery.

I don't know much about the pre-2004 Prii, but I didn't think the Prius had an ICE driven alternator, therefore is shouldn't be necessary to "drive around until you're charged". If the 2001 has an ICE driven alternator, then I suppose this is good advice, otherwise you need a service tech to look at it who understands that the electrical system in a Prius isn't the same as in a non-hybrid car (find a new service tech).

A reasonably good tech should be able to determine rather easily if something is draining the battery while the car is off.

A reasonably good tech should be able to determine if the charging system is sending current to the battery.

A reasonably good tech should be able to determine if the battery is capable of holding a charge.

Such a tech should be able to at least tell you which of these are the problem.

Come to think of it, I'm a bit confused as to why you haven't been able to get this information yet.

Perhaps there is some other possibility I'm not thinking of.

 

Go to

http://www.trilug.org/~chilcote/ToyotaPriu...s-controls.html

Bring up the screen that reports 12V battery values. Tell the forum here what the values are before starting, after starting but before engine turns on, and then the value after engine turns on. This will help a lot.

 

<div class='quotetop'>QUOTE(musician @ Jul 26 2007, 12:24 PM) [snapback]485467[/snapback]</div>

If you have reached the point where you need a jump to start, you are right, no screen till started. At least you know you can read the 12V value if the car is on. Go to:

http://www.elearnaid.com/12vobaforpr2.html

This is one way you can see how a good 12V battery behaves.

You are right about the starting behavior. For the early Prius, the ICE always starts at turn on to get the engine to emission control temperature as soon as possible. When the engine has been running, then turning the car and back on again real soon causes the engine to run for just seconds if at all before shutting down. The later models (04 and up) delay the engine start till the hot water tank has warmed up the engine so there is always that delay between turn on and engine starting.

 

<div class='quotetop'>QUOTE(musician @ Jul 25 2007, 10:59 AM) [snapback]484698[/snapback]</div>

Just leave it in the driveway in Ready mode for 5-6 hours, if the battery is any good that should bring some life into it. No need to drive and waste gas.

Wayne

 

<div class='quotetop'>QUOTE(musician @ Jul 27 2007, 12:31 PM) [snapback]486155[/snapback]</div>

That is the right voltage for the inverter to be charging the battery. Either you have a bad battery or something is draining the battery after you turn off the car. One way or another someone has to get an reading of how many mA or Amps are being drained when the car is off. Your problem is easily debugged by a good auto technician. Now you just need to find one or become one. Any courage to run the battery test on the link posted earlier?

 

Even if it's the "updated" battery for the NHW11, that could be
gettin' kind of long in the tooth by now for 12V lead-acid. I'm
even starting to get a little paranoid about my '04 vintage one,
although it's been successfully running my fan hack during a night's
sleep without ill effects over the last few days.
.
_H*

 

Once a lead acid battery gets sulfated, it has a dramatic reduction in capacity. Usually the best option is to purchase a new battery, FULLY charge it with a good automatic battery charger, then install it. Toyota - naturally - recommends their fancy-schmancy 10 amp automatic "Toyota" branded charger, which is made by Associated. This tsb applies to the +2004 but should give a clear idea of what is needed

The short driving cycle I go through, and the first winter of many -40 nights and constant electric defrost use, left my 12 v battery severely drained. I had purchased several VDC Electronics Battery Minder units at auction, and decided to try one on my Prius. It actually works quite well and I haven't had a problem since. Not sure though if I would pay $70 for a new one, that is a bit steep

http://www.vdcelectronics.com/batteryminder_12117.htm

For example, I was gone for two weeks on vacation at my hobby farm. I took the FJ Cruiser and left the Prius in the underground parking. Got in Sat and the Prius powered up just fine.

If you're curious, here are some photos of the harness from my battery out the hatch. I have flexible plastic conduit covering the wire, but for the photo I removed the conduit