Where Is The 12V Battery On A Gen5 HEV?

3rd gen battery is under the hatch floor.

The pic you attached (from gen 5 owner's manual?) is highlighting the jump start point. The aforementioned stud-and-nut that feeds 12 volt into the fusebox is elsewhere in that pic. Have a look at the video I posted. Again, the video is of gen 3 underhood fuse box, but gen 5 may be similar.

For an onboard charger running the 120 volt power cord out through the front grill seems sensible. Parked outside, you're able to leave the hood latched, are just running an extension cord out to it.

If on the other hand you were running a quick connect out to an external charger, there could be disastrous vandalism: it's basically a two-pronged connector, with the prongs connected to neg and pos battery posts. Someone putting a jumper wire between the two pins would short the battery. Even heavy rain might short it.

 

I don’t think permanently mounting it will help you or save you time. You still need to open the hood, carefully route the AC cord through a gap over the headlights, plug it in, and then close the hood, which will take quite a bit time. If the car is rarely used, it is less reason to mount it permanently. That is what I do when I go on a vacation. I close the hood over the AC cord routed through the gap in the corner of the headlight. That way, if someone breaks into the garage, the car can’t be vandalized or its parts stolen, or animals and dust can’t get into the engine compartment.

Also, in Gen 5, the terminals under the hood will be safer to use than the battery terminals. If you want to use the repair mode, don’t forget to disconnect the negative terminal of the battery in the trunk.

 

To try to partially rehabilitate a battery that saw a deep discharge. Lead–acid batteries degrade if the state of charge drops below about 50%.

 

Thank you, everyone for all your advice.
For what it s worth, the car I'm dealing with is a gen 4, but I am assuming there isn't too much difference between that and the gen 5. I'll see when I get in to it further.

I was hoping to be able to simply substitute the wiring from the charger to the car, but it looks like the cable is hard wired on one of the boxes. Changing brands makes that more difficult. I like the idea of connecting to that stud, as I wont have to disconnect the battery. I would like to avoid bringing the charger's AC connection, out of the front of the car, as it seems unwise to drive around with that socket exposed to the elements. But since I keep the car wrapped, it may turn out to be the best solution. I should be able to mount the charger some where in the engine compartment, as that is where the current one is.

 

Run the power cord out through the grill?

really?

 

Mine is a Gen 4 Prius Prime, too. See my post above on what to do with the AC cable. You don't need to mount the device permanently. Disconnecting the negative terminal of the battery if you have to doesn't necessitate anything other than resetting the radio stations.

 

Meh, a cord dangling from the grill? Perhaps it is OK on a 1990 Dodge but no way in a newer car. Also, what about the grill shutter?

Regarding someone messing under the hood, better safe than sorry, right?

 

Not a very hard and fast rule. Sometimes it can steer you into crazyland.

 

When you leave a cord to flap in the wind, it breaks the wires inside. I think a lot of people think they have a block heater when they don't.

 

I know, so gauche.

 

Again, aesthetics aside, you are blocking a lot of air flow, and Gen 4 and Gen 5 have active grill shutters.

Moreover, for someone like the OP who almost never drives the car, I don’t see the point of a quick-connect plug.

 

Thanks. That's what i thought from checking out that fuse box diagram pdf some bdoy posted.

 

My car came equipped with an external connector for the block heater. I could use something similar for the battery maintainer, but I find it less intrusive to close the hood with only the plug end exposed.
Besides, with the external connector, you have to stow the special cord. It's much easier to plug an extension cord to the exposed plug.

 

What you don't see clearly is the notch you have to cut in the fuse box for the cord.

 

Well, my saga continues.

I have begun to look into this a bit more seriously. I have discovered why the battery drained down. The idiot service tech at the dealer never connected it to the battery at all. The "installation" consisted of putting the charger in the car and tie wrapping it down. No connection whatsoever to the battery. There should be an IQ test for some people to go out of the house. I haven't checked to see how much the dealer charged for this tie wrapping service.

Also, the Gen 4 fuse box doesn't have the stud directly connected to the positive battery terminal as recommended by Paul.

I finally broke down and actually read the manual. This model doesn't seem to bring out the positive terminal anywhere. Their advice when jumping, is just connect to the batteries themselves.

So, I'm back looking for the place to tie the new box in. I'll probably wind up disconnecting the battery, as I hoped to avoid.

Again, thanks everyone for your help.

 

I have the same car (a Gen 4 Prius Prime) as you do, and I don’t know why you make something so trivial so difficult. It takes two minutes to hook up the Noco Genius to the battery. And you need to do it rarely because you don’t even drive the car. Just hook it up, close the hood over the AC cord, and leave it in there loose.

 

That is generally the SARTING for any project on an automobile.
actually reading the manual.

 

This is an onboard-style charger? And being a 4th gen the 12 volt battery’s under the hood? You could connect the charger’s positive (red) wire directly at the battery’s positive post, say under the bolt head of the battery’s positive cable clamp. Similarly, connect the charger’s negative (black) wire under the head of any nearby bolt going into the car body.

that’s an AC power plug? Nothing will happen if it gets wet. Think it through: take any electrical appliance in your house, pull the plug, lay some conductive metal across the prongs, what happens? Nothing much.

that said, to keep the plug clean and reduce corrosion, there are caps available, often AC plugs for this sort of application include such caps. There is one in the block beater cord pic I posted up the page, a little difficult to see. Better pic:



^ Note too the double zip ties: sooner or later you will forget to unplug, so to avoid dragging a cord down the road, and/or driving over it in a curve, you want to really secure it, and use an extension cord that easily pull off.