12v end of life symptoms

While I'm pretty familiar with the catastrophic/sudden death symptoms of 12v battery failure I don't recall a lot of posts from folks who's battery has suffered a slower (?more painful?) death.

Background for the question:
Yesterday: Had the classic symptoms of the old '04 MFD failure (A/C disconnected, no touch screen function, etc.) all onset right after a car wash. BUT, I'd also pulled my Ipod out of the DICE while the car was on and the MFD seemed to work just fine after I disconnected the DICE. Ultimately I reconnected it and all was still working fine on the MFD.

Yesterday evening: Updated the CAN firmware on my CAN-View...that seemed successful, but I just plugged it back into the connectors without restarting or programming it. Didn't turn on the Prius until....

This afternoon: I went out and put the Prius into IG-On mode specifically to program the CAN-View. Everything loaded up just fine and I was going though my custom settings and getting the display how I wanted it.
Here's where it get's interesting:
Then, suddenly, I got the red triangle of death, a message flashed on the MFD that there was a problem with the 'Park mechanism' and that I should pull over and put on the parking brake. Dash showed the triangle and CEL, MFD showed just the park and put on brake message. Remember I wasn't even in READY mode when it did all this.
I tried multiple things, first, I think I tried the brake/Power button to try to get into ready, but that didn't work. Then, several times, I tried shutting down and powering up to READY. I could never get into READY and could never get into gear even though the dash would light up, but the MFD stayed black as night and could not be powered on. Also, after the first attempt to power up I completely disconnected the DICE and CAN-View.
At some point I discovered that I'd unplugged the red connector from the OBD-2 connector under the dash and had been trying to program the CAN-View while that was disconnected (could that have caused all this?).
I also noticed after 2-3 attempts at getting into READY that the digital clock on the dash was quite dim, the battery relay clicks seemed 'softer' than normal...less assertive if you will. The idea that maybe the 12v was dead for some reason hit me. So I got my little jumper thingy and sure enough it started right up off of that on the first try. The ICE kicked in and all seemed well.

I reconnected the CAN-View (not the DICE, I think that's screwing things up a lot for me and didn't want to introduce unknown variables) while the car was running and went to get the kids (took the jumper box with me!) Since then everything has worked fine. I have had the car parked for about 4 hours now and haven't tried to restart yet. I'll probably wait until tomorrow at least, and maybe until Sunday when I have to head home from the lake.
I did call the Toyota dealer and they have the 12v in stock (said it was $90 which seemed way low to me).

So, has anyone else experienced a slow battery death and was it anything like this? I know I've got a lot of wierd variables in there with the DICE and CAN-View, but the fact that it jumped off the pack so easily after I sat in IG-ON mode for 5-10 minutes seems to suggest it could be a weak battery issue.

Other things, the CEL and triangle of death cleared after 3 restarts. No DTCs were stored (according to CAN-View).

Would you wait and see?
Go to the trouble of pulling it out and testing it?
Just shell out the $90 to replace it since it's 4 years old and will die sooner or later anyway?
Would you replace it yourself or get the dealer to do it. I'm very much inclined to do it myself, I know where it is, can't imagine why I couldn't do it myself...though I'm not too excited about reprogramming the windows, NAV, etc.

 

Thanks Nikki and Doug (and Doug), I agree that the most likely thing is that the DICE and CAN-View are red-herrings. The CAN-View on my "with NAV" model does connect via the NAV so could do some pretty weird things, potentially, to the MFD, but I don't think it should have caused any kind of 'no-start' or "park lock mechanism" issues. Just wanted confirmation.

I almost picked up the battery today, but was a bit tight on time. Guess I'll grab it on Monday and pray they don't figure out it's supposed to be more than $90.

Will report back, will probably photograph the install while I'm at it since I've already gotten one good tip (disconnect from body instead of battery) and to document the vent tube and how to disconnect/connect it.

I think I'll have definetive confirmation on whether it's the battery when I try to start up Sunday morning (no plans to drive it before then unless something comes up...I use the electric golf cart here at the lake), if it won't start then I'll know for sure. I've got my jumper box with me and charging as we speak. I also double checked that my daughter hadn't flipped on the dome light or that a door was ajar or something.

 

<div class='quotetop'>QUOTE(qbee42 @ Sep 22 2007, 10:24 AM) [snapback]516173[/snapback]</div>

Great Idea! I'll try that.
BTW, just to update, we decided to go to breakfast this morning and took the Prius. It started right up (sat unused for about 15 hours). So I may wait a bit to get the new 12v.

 

<div class='quotetop'>QUOTE(KD6HDX @ Sep 22 2007, 11:49 AM) [snapback]516188[/snapback]</div>

I'm still betting the price quoted off the top of his head was wrong, but hopefully not.
Any issues getting the battery installed? Any other tips for me? Did you disconnect the negative wire from the body or were you able to get a wrench on it at the battery (what tool did you use?).

 

The transplant was successful! The Patient was maintained on life support via my emergency jumper/inflator/light box during the battery exchange and there was no loss of presets.

It is a bit of a PITA to get the battery out as there's a lot of stuff to disconnect and move out of the way, but it went pretty well...not even any sparking (those electrical sparks make me whimper like a baby). I appreciate all the advice given on how to do it, esp. the idea of putting the jumper box on to maintain the car during the exchange. The photos at Hobbit's site were a huge help as well. Haven't checked the voltage of my old battery yet but it had been functioning normally since this original post...may well have had several months or more life to it, but I feel better putting in the new one and knowing it'll likely last the rest of the time I have the car and that it's very unlikely I'll be stranded anywhere due to a premature battery death.

 

<div class='quotetop'>QUOTE(Betelgeuse @ Oct 15 2007, 03:28 PM) [snapback]525986[/snapback]</div>

~$150