2010 Gen 3 Prius and 12V Battery Question

One 3-prong 120 volt male cord zip-tied in front/lower grill for the block heater, and a proprietary CTEK quick-connect cord with fuse, wired into the 12 volt positive terminal under-the-hood. With the latter I pop the hood and connect to adjacent wall-mounted charger.

 

You know, I had just assumed you'd connected the CTEK to the battery itself. Where's your ground connection for the CTEK? Do you leave the actual unit mounted in the engine bay or does that part stay in your garage? Apologies if you have a thread somewhere with these answers...I didn't find it.

I'm probably going to have a hard enough time convincing my better half to plug/unplug one cord, let alone two. Also, we park outside so leaving the hood popped (or popping it when its snowy) isn't an option. Maybe something like this and find a place (behind driver DRL?) to mount the trickle charger:

 

My father just told me he switc

The multimeter reading is with the car completely off.
When I say "car off" at the Diagnostic screen its from a single push of the power on button foot off the brake (accessory mode). I do realize that accessory mode pulls more power than just being off.

I edited my post for clarity.

 

I thought answers were in what you just quoted lol. Anyway:

Positive connection of the quick connect is per video 23 (by @NutzAboutBolts), and negative (aka ground) connection is at a convenient adjacent threaded hole that I dug up an M6 bolt for:
And block heater AC cord. When not in use I just tuck it in between grill slats, friction holds it:

 

Thanks for posting those pics Mendel. I was curious if it connected to the front of the car (jump posts) or in the back. Seems like an easy enough setup to deal with!

 

For the record:
I park in a carport, with no nearby AC outlet. I've attached the Ctek pigtail to the terminals of my 12V in the back. I just leave the Ctek back there in the right hand corner and run a long outdoor extension cord from an external (GFCI protected) outlet to the rear of the car, plug the extension into the Ctek, and close the tailgate on the cord. The tailgate gasket is plenty thick enough to accommodate the cord.

 

Just curious, would a solar charger work in your situation?

 

"would a solar charger work in your situation?"

Perhaps, if you could get the 12V to recognize a USB connection (doubtful) and were willing to wait, like, FOREVER, and if you could determine if the charger were 'smart' (ie, NOT a trickle charger).

Conclusion: I'd never try it...

 

What I meant was hook up a 12v solar charger to the 12v battery.
Then you wouldn't need the long extention cord.

 

"Then you wouldn't need the long extention cord."

I don't see how the extension cord is a problem that needs to be solved...It's inexpensive, and I already HAVE the excellent Ctek.

 

Sorry, I was just curious...

 

I left a mere 5 watt solar charger sitting on the windshield of $previous_vehicle while waiting to sell it, kind of clamping the cord under a windshield wiper, and it did a fine job of keeping the battery from going flat while it sat there. ($previous_vehicle did not have SKS or much else in the way of power-off battery drain to contend with.)

 

A nearby VW dealership was doing that, with pretty much all the cars on their lot. Seems a good ploy in the absence of convenient 120 volt.

 

See attached...

 

Solar panel discussion has me wondering if I can use the big one on my roof that came with my car to trickle charge my 12v!

 

Well, have we got the thread for you!

 

Okay resurrecting this discussion because I forgot I gave away my old 12v already so I cant hook an extra battery to the front of the car.

My father claims he replaced the 12v in his lexus hybrid without resetting computer by just clipping a jumper cablefrom the new battery to the car leads (so for a breif time there were two 12v batteries connected in the back of the car), and then unhooking the old battery, and then hooking connections to new battery and disconnecting jumper cables.

Does anyone have any conjucture on if this is proper procedure? Any dangers of having two batteries connected at once? Like I said earlier, I'd rather not reset my computer if I can avoid it.

 

That would be tricky; it only takes a split second interruption and memories would be lost anyway. And it is no big deal; I do it purposely every time I do brake work. AND, there’s an outside chance of mixed up connections and something “bad” happening.

there ARE OBD memory saver cables readily available; i use one with a jump pack.

 

There isn't any specific danger in having the two batteries connected at once (as long as you get the polarities matched!).

There are all of the usual dangers of doing your battery removal/reinstallation 'hot'. You shift your grip on the battery and one of the posts or cable clamps bonks against the sheet metal or a tool falls on it and sparks fly.

Or you are super careful, rehearse all your motions twenty times, tape plastic over everything that could accidentally touch, and you succeed in not making any sparks fly, but halfway through the operation one of your cable clamps simply slips off, and you end up having to reset the stuff anyway.

There is something I haven't tried before, but might someday.

Gen 1 and Gen 2 had very convenient unpluggable connections at the positive battery clamp. If you ever wanted to unhook the battery, you didn't have to go find a wrench for the clamp on the battery post, you just unplugged the cable. It seemed so very civilized.

I was very disappointed when I found the Gen 3 did not have an unpluggable connection back at the battery clamp.

But that was because I had not noticed (and it took me until this spring to notice) that the big fat white wire plugged right in at the front of the underhood fuse box is the battery cable.



I mean, sure, I had noticed the fat white wire there before, but I had never looked up what it was. Sure enough, it's 1E, from the Frame Wire, the cable to the battery.

So the thing I might try is: get a spare battery to hold the settings up, and some clamps, and attach it under the hood (to a good ground point, and the jump terminal at the top of the fusebox).

Once that's in place, unplug 1E, then go around the back and do the battery replacement. You still need to undo the ground cable there first to minimize your chance of making sparks fly, and reattach the ground cable last to the new battery, but at least when you have the positive clamp removed it isn't still hot from your battery up front. And because the other battery is connected up front, you're less likely to disturb those connections while you're hauling on the battery in the back.

Once everything is buttoned up back there, go back to the front, plug 1E back in, then unhook your supplemental battery.

 

It would be safer to attach a good battery to the terminal in the fuse blox under the hood, and ground to the chasis.
Remove the ground from the bad battery(in the trunk), then the positive and wrap the cable in a clean rag
or towel so it won't ground to the chasis while you remove it and install the new battery.
Then you won't lose any settings.