HELP ME OUT: I went on a 4 month trip. Got back and my 2008 PRIUS has a 'dead battery'. How do I open the HATCHBACK, so I can get to the 12v battery and charge it? Do I have to do any RE-programming after the battery gets charged?
It is a ridiculous procedure that you have to do. You now have to put down the back seat in order to get to the hatchback area. You then have to crawl back into that area and I believe take out the floor piece that is covering the spare tire. (But I'm not 100% sure about this.) Then I believe you have to remove a little plastic piece there by the driver's side. You will then reach in with your slim fingers and somehow, without being able to see it, and having never seen it before, touch and move the little hatchback opener. The method is explained in the owner's manual, if you have access to it. Now, that is the hard way. IF your 12v battery isn't stone dead, you may be able to hook up another good 12v battery positive terminal to the positive jumper post in the engine compartment, good 12v battery negative terminal to one of the exposed bolt heads there, and then be able to open the hatchback the usual way. One MAJOR concern with "the easy way" though is that people have reported damaging the very expensive ECU if it is incorrectly jumpered, although I can't imagine how that could happen. Also, the little jumper post is very small, and seems to me impossible to hook up to regular jumper cables. And, if you choose to do it this way, and if the other battery is in a vehicle, I would not have the other vehicle running at any time during the procedure. Upon doing either of these procedures, you will never allow your 12v battery to go dead again. Or at least, if it does, you won't have the hatchback shut. One additional bit of bad news is that if it is the original battery, and after 4 months, it is probably stone dead. If you have the opportunity and a few days, the eLearnAid battery and kit is the way to go.
If you wish to open the hatch: 1) Lower the rear seat back so you can crawl into the hatch area 2) Remove the folding carpeted floor panel 3) Note that the black plastic tray over the spare tire has a small access door that faces the hatch latch. Open that door 4) Stick your finger into the hole and find the little metal latch release. Move the latch, then see if you can open the hatch. The reprogramming would involve setting your radio station presets and enabling the driver's side window auto up/down.
As has been stated by others, jump the car from under the hood, which gets the electronics going, and open the back hatch. Much eaiser. Charge then as needed.
The jumper "post" is the large rectangular tab folded over the back edge of the + access compartment -- behind the small screw post [to which I suspect you are referring] -- and it accommodates most normal jumper cables. See [third picture]: http://priuschat.com/forums/gen-ii-...-low-power-empty-battery-pack.html#post964157 The small screw post can be handy to use with smaller alligator clips -- clips that may slip off the large tab -- when, for example, attaching a 'keeper' battery while changing the main battery.
Overnight charging works just as well from the jump points under the hood, unless you have a crappy old fashioned charger that might hurt the electronics. If you do, you probably don't want to charge a Prius battery with it. You will kill the battery. Tom
Wow, I didn't know that!!! Thanks. But I would still be very, very careful trying to hook up full size jumper cables there. I have fortunately never needed to emergency jumpstart the Prius, but I have tried to restore power with a dead battery, just as ski.dive is trying to do. I still think it wrecked my little Battery Tender Jr., but I can't prove it. The battery was stone dead, I had tried hooking another battery to it and then removed it and tried the charger, and nothing worked. The dashboard was lit up, making noises, and I thought I wrecked the car so I disconnected everything. Once the new battery replaced it everything was fine.