Auxiliary Battery Replacement

anyone had to replace the AUX battery on 04 models and above? i may be the first soon any custom kits instead of pricey toyota OEM parts?

 

<div class='quotetop'>QUOTE(efusco @ Oct 7 2007, 01:37 PM) [snapback]522487[/snapback]</div>

Evan, with mine being an 06 I don't expect my 12V battery to be replaced for awhile but I am curious about the install. Have you checked into any problems in a swap out? I was wondering what programming or memory items in the various computers/ data bases might be lost (if any) during the voltage loss in the time period when the old battery is out and before the new battery is installed? I have no problem with resetting a clock but for some of us, we have large data bases of special waypoints in the nav unit and numbers in a phone book that I would not want to reprogram!

Best wishes.

 

<div class='quotetop'>QUOTE(mecram1 @ Oct 7 2007, 11:49 AM) [snapback]522454[/snapback]</div>

If you feel better about hooking it up, I would.

But an AGM battery "vent" is really just a safety valve. Unless you overcharge the battery, it stays sealed. No hydrogen will escape.

 

I actually just replaced my battery in my '05. For a battery replacement, talk about a pain in the @$$! I bought the OEM battery from my dealer for like $150... <_< . I started by just pulling the positive cable off, and covering it with the little plastic covers that come with the new battery. Then I did the negitive by unscrewing it to where it was attached to the car, since it is impossible to get a tool in that little space, but it was no big deal. Make sure you tape the end so it dosent touch anything or else it will throw sparks. Then I took off the black box sitting next to the battery, breaking system I believe? Not quite sure, but just a couple screws and moved it out of the way, keeping it pluged in though. then I loosened the battery bracket, which also holds another small box that connected to the positive. Then I had to remove a section of the HSD battery's ventilation... then finally she was ready to come out. Slipped the old battery out, and reversed everything to get the new one installed. Works real well, just a pain that it has to take close to an hour just to change out the aux battery. Once in, i turned on the car, which acted wierd the first time I tried to boot it up. It came up with the red triangle and didnt turn on fully. I just turned it off, waited a second then tried it agian and it was fine. I checked my settings on my nav and they were lost, but I do save them occationally to the "user 1" slot. The user preferences were not erased so I just changed it to "user 1" and everything came back. I turn off my reverse and seatbelt beeps, which I had to do again. Clock needed reset of course. Other than that, everything was fine.

 

It's good to try and do *something* to keep the ECU standby memory
alive in various places, because not only do you not lose your power
window stuff, radio presets, and NAV options, your engine ECU doesn't
have to re-learn fuel map trims and the like. So unless you're doing
serious ECU-connector pulls for whatever reason [EV switch?], leave
as much with its off-state 12V as possible...
.
_H*

 

<div class='quotetop'>QUOTE(efusco @ Oct 7 2007, 02:37 PM) [snapback]522487[/snapback]</div>

Good Dr.,

Lead acid batteries don't store well. You have to keep a float charge on them or they will fail in a few months.

I would suggest, since you've already paid for the battery, that you replace it. That way, it won't destroy your new battery while waiting for your old one to die (at which time you will have two bad batteries).

 

What a royal pain! My (daughter's) '05 aux. battery apparently died, and we fought with it for a good hour before we lost sunlight and had to quit for tonight. I think I'll take Slair's idea, of disconnecting the negative where it attaches to the car, since that's the last connection, and we gave up trying to get out the bracket connection. I particularly appreciate the mention to cover the connections, since the new battery will have an actual charge.... At least when we get this done, I'll know what to do when my (husband's) '04 needs a new battery, or my '07. Adding to the frustration, once the auxiliary battery dies, you can't get into the trunk from the outside, you have to climb in and release the (really well hidden) latch. Definitely not an easy diy project (unlike the cabin air filter, which takes an entire 30 seconds to change). My dealer also charged $195 (plus tax, over $200) for the replacement.

 

If $195 was the parts dept price, that is outrageous since MSRP is $139.

Yes, you should disconnect the negative cable where it attaches to the body. When removing the positive cable, you don't have to remove the red plastic cover, just bend it up enough to gain access to the terminal nut.

For your other two Prius you may consider replacing the 12V battery after four years of service, so that you can do the replacement at a time and place of your choosing, rather than waiting for the battery to die. Good luck.

 

I accidentally drained my 12V aux battey in my 2005 Prius. Since the car has 154K on it, I started doing some preliminary research on replacing the aux battery. I jump-started the car and went into maitainence mode to check the battey health, looked like all the numbers were still good, so I may put hold on replacing the battery for the time being.
I appreciate very much so many good posts ranging from buying/replacing with the OEM Part #28800-21171, DIYing with Optima YT D51 and several other small marine/auto batteries. I would like to share with you one really low cost ($66) DIY option:
Please see Costco Item 201864, it is a D51, CCA 500 (not relevant), RC 85, 9.3125 L x 5.0 W x 8.6875 H (inch). I believe Optima D51 (D51R) has almost the same demensions (with/without post height). You will need D51.
I went to my local Costco and only saw D51R (Costco Item 12881, I took several pictures, costs $66, I can email to you). I did measurement on the physical battery: 9-9.25 L x 5 W x 7 5/8 H w/o post (inch). For you DIYers, you will need terminal adpater kits and it will be fairly easy. Also it is sealed and I can't find any vent opening/connection on the battery (Please comment). Also please broadcast which Costco you find that carries the item 201864 (Kirkland Signature Lifecycle Fitment Code 20).
Thanks and Happy DIYing.

 

The pictured Costco battery appears to be of the traditional wet-cell design. The vent caps will pry off so that you can add distilled water as needed.

One problem with the pictured battery is the terminal polarity is reversed from the correct battery. This means that after installation, the positive terminal will be within a couple of inches of the inside of the right-rear fender. If that fender is hit in an accident, the sheet metal fender may short out the positive terminal which results in a potential fire and safety hazard. Further if the battery case is damaged in the accident this may result in battery acid being released into the hatch and rear passenger area.

 

" I went to my local Costco and only saw D51R (Costco Item 12881, I took several pictures, costs $66). You need D51, Costco Item 201864.

 

Optima now sells a direct replacement, DS46B24R. MSRP is $199. As more retailers i..e Amazon, elearnaid stock it, I expect to see it in the $160 range. Yes, you can do the low-rent wet cell, but there is a safety trade-off to be aware of.