Will a portable jump starter work on the PiP?

Absolutely!! Just make sure you drain the jump starter battery once a week. Lion batteries don't like being left charged all the time.


Unsupervised!

 

great idea!

 

BAD advice.
Where exactly did you get that little tidbit of totally incorrect information ?

It should be connected to it's charger every few months when not used but it is NOT necessary, or recommended, to purposely "drain" it.

P.S. If it has the right connectors available, they are also useful for recharging things like phones and tablets.

 

You can jump start a Prius with anything that has 12 volts. You are not mechanically turning the engine, so you don't need much power. You are just powering up some circuit boards. I used the battery out of an emergency light one time, it worked fine. Just make VERY SURE not to jump it backwards.

 

My experience today was my jump start power pack would NOT start my Prius using the under hood positive connection and ground, (dead battery due to trunk lid ajar, draining starting battery to less than 4 volts. Away for two weeks!) Battery chargers both shut down due to extreme low voltage. Could not access starting battery as trunk release would not work with dead battery. Connected the charger to a spare 12 volt battery & connected the spare to the under hood contacts with jumper cables and slowly recharged the starting battery. Once charged the car started however the “Check Hybrid System - stop vehicle in a safe place” warning came on with the yellow triangular warning light. Calling Toyota and they informed me there was something wrong with my hybrid system and they could check and diagnose the problem for only $145. Instead I disconnected the starting battery for a minute then reconnected it and presto, NO warning light. I believe if I could have accessed the starting battery, I might have been able to jump start my car.

 

You can open the driver door with the mechanical key, crawl to the back, lift the deck board, pop the little cover over the inside hatch release, and pull that to open the hatch and access the battery.

However, I don't think that would have changed whether you could or couldn't start with the jump pack.

There is one thing I'd recommend checking with the jump pack. Look closely at the alligator clamps on the ends of the cable. Do they have little copper teeth on both jaws? (Mine does.) But, are the copper teeth on both jaws actually connected to the cable? (On mine, they are not; only one jaw is—appearances can deceive!).

The front jump connection in the fuse box is also only copper on one side. So guess what happens if a one-sided jumper clamp gets clamped onto it, facing the other way....

a whole lot of nothin'.

-Chap

 

Thanks Chap I need to check mine out. I hate it when things aren't fool proof.

 

This is absolutely false. You're thinking of the old NiCd batteries, which undergo a chemical change that reduces their cell voltage with continual charging--deep discharging allows this reaction to reverse and the cells to recover from this "memory effect".

Lithium cells, however, MUST maintain a reasonable charge during storage to prevent reducing their recoverable capacity. There is no problem with continually charging lithium cells with an appropriate charger. Deep cycling lithium cells will reduce their life.

 

This is what I thought, too, until yesterday.

You still need a decent amount of current depending on the state of the AUX battery. In my case, the AUX battery is 6 years old, and the car is getting very light use now (kids away at college--cars sits in driveway most of the time). I attempted to use an AC-powered 13.8V power supply with 4-6 A capacity, but the fuse blew when attempting to start. I was about to start up my portable generator that supplies 12V at 8A when my neighbor happened by with one of those portable jump starter/compressor products that worked right away. The problem was that the AUX battery was in a low enough state-of-charge that the system needed more instantaneous current from the jump starter battery. Batteries work better for that than power supplies, since power supplies generally limit the instantaneous current available, whereas a battery can better supply higher peaks (at a reduced voltage) briefly.

 

That's interesting, although a headache for you. I had to jump mine yesterday (6-year-old AUX battery, car sits around a lot with SKS enabled), and one of those portable jump starter/compressor products worked just fine from the jump start terminal under the hood (and no warning messages). I'm wondering why your spare battery hooked to that terminal didn't work for you. The success of that method probably depends on the state of the AUX battery--mine might not have been quite as dead as yours, although it did measure at around 4V or less.

 

I'd suggest, sometime when you are not feeling rushed and have a few minutes to spare, you could learn the location of the inside hatch release, so you will have that option at some future time if the battery is dead and you want access through the hatch.

-Chap

 

I have a battery charger that claims to automatically adjust between 6 and 12 volt batteries. Attach it to a 12V battery that is down to 4 volts, and the charger brings it up to about 7 volts and declares it done! I had to buy another charger without the automatic 6/12V adjustment to get past the 6V battery identification.

 

This is EXCELLENT advice. My daughter has use of her dad's Prius. Of course it sat for 3 months with no use (COVID-19). We have a cheap EverStart jump starter, and had trouble getting it working. I thought it odd that the Prius "+" terminal wasn't *all* metal, but metal on only one side, but it didn't occur to me that that could be true for the clamp as well. The Prius was so dead that it took several tries with the jump starter (and some charging of the jump starter in between attempts) but at least once we were getting it hooked up correctly every single time (clamps should not be one way !!!!) we made progress and eventually got the thing started. Thank you so much for this advice. It was also great that my daughter and her mom (me) were able to solve this without outside help. She is 17 and I want to empower her for the future ... Thank you!

 

Better test, charge and/or replace that battery; a jump start is not a panacea for a neglected battery.

 

It will at the very least need a full recharge, which in a Prius takes many hours in READY, not just a quick drive.

If it hasn't been otherwise abused, there may still be decent life in it after just one mishap and one jump.

PiP owners: will it charge the 12 volt battery while plugged in?

 

In my experience, it will only charge the 12V battery while the HV battery is being charged. I don't see any 12V charging once the HV battery is full, though I have not monitored it for long periods of time.

Other PHEVs and EVs do some 12V maintenance when left plugged in, I'm not aware that the Gen 1 Prius Plug-in does.

 

My tests on my PiP gave the same results as what @QuantumFireball said. It only charged the 12V while it was charging the traction battery.

 

Had to jump my Prius plugin with my motorcycle when accidentally leaving the dome light on. Apparently, there is a way to open the trunk when the battery is dead but I haven't figured it out yet.

 

you can either put 12v to the jump point under the hood, or crawl into the hatch with flashlight and a small blade screwdriver. pop the door off the inside and pull the lever while pushing the hatch door.