Greetings everyone! We recently picked up a 2026 Prius PHEV and I wish to add a 12V battery tender harness under the hood. I have added these to other cars and placed the connector so that it pokes out at the lower windshield area for easy access. Looking under the hood of the Prius, Toyota does not make it easy to attach a ring terminal to the remote positive battery point inside the fuse box. It looks like Toyota designed this for alligator clips and not a ring terminal connector. I poked around and discovered that the positive metal piece extends all the way to a nut and bolt. I tested whether or not there is power going to this nut by using a battery tester and it powered up! I believe it is safe to connect the ring terminal of the battery tender harness to this nut. What do you think?
It worked! FYI, the Toyota 12V battery in my car is a GS Yuasa 345LN1-MF. Contrary to some info on the web, this is not an AGM battery as it is a maintenance-free (MF) lead-acid battery.
Is there a reason to do it up front instead of through the back hatch? I installed mine directly to the battery and ran the wire under the battery cover. When in regular use*, I run it out the bottom of the hatch opening and close the hatch on it leaving a little pigtail out to connect to. When not in use, I hide the short cord in the corner of the cargo area next to the battery cover. I'm having a hard time understanding how a cord coming out of the windshield area is a nicer and easier install. It seems like it would be ugly and flapping in the wind while driving, or else you'd have to open the hood every time you wanted to use it. By placing it in the rear hatch, you can leave it there even while driving and it's no issue. *in the winter, I might plug it in more often and just leave the connector dangling out between charging(it's weatherproof)
Me too. Also there's some windshield defroster wires in that area. I don't think it would be a problem but the manual says be careful about touching that are when it's running.
I’d be cautious about having the 12 volt quick-connect exposed: a joker with a paper clip or copper wire could short-out the battery. Even rain might do it. Some quick-connects have an inline fuse, good, but still.
It's a great way of NOT driving-off and ripping things out of the wall; but that wouldn't be my first choice either. Great for a garaged car; but questionable for one exposed to the elements and potential for connection bridging from moisture or snow. I'd place it under the hood. Hood up = plugged-in, hood down = ready to travel. YMMV
Thank you all for your replies. The car is garage kept and there are several reasons why I added it where I did. I don't have much clearance to lift the tail gate with the garage door closed as it will come into contact with the hinges that span each section of the garage door. In days gone by, I once drove off with the tender still attached and ripped it right out of the wall socket I have tied a yellow micro fiber towel to the tender's power cord which hangs from the garage door opener. There is absolutely no way I can forget to disconnect it before driving off - I'm old And yes, there is an inline fuse on the tender's harness wire. Lastly, I find it much easier and convenient to connect and disconnect it from that location.
I do the same thing Hammersmith does and connect to the battery in back and run the connector out from the cover. When I need to charge I run the cord out the back hatch, close the hatch.
