Hybrid Battery Replacement or Not

Is your mechanic a hybrid mechanic with the right tools to read the codes on the car? I have heard and seen many mechanics misdiagnose a Prius problem based on a "triangle of death" is on. That light can go on for many reasons, one simple one would be a car that's low on engine oil.

A 2007 is probably going to have a battery failure at this point, but you should make sure that the code he pulled actually points to a battery problem. A hv battery failure usually is accompanied by many dash lights that come on

 

Those be your options .

But I'd make sure the codes are right before dropping hard cash money on the solution.

But for 1-3 years either option 1 or 2 will get you there.

And after that, maybe you get more life out of it and are happy to boot .

 

Option 3 would get you there too as long as the donor pack was 5 yo or less and in good working order when wrecked. No rebuilt will get you there unless the rebuilder used a complete module set from a 5 yo or less donor pack. If they have one of those you will pay a pretty hefty premium getting close to a new pack option. DIY will save you that labor and premium.

I'd also make sure the codes are right before dropping hard cash money on any solution.

 

Thanks for this. I'm not sure he's a hybrid mechanic. He's focused on working only on Toyota's and Lexus's.

Oil level is fine.

Would it be a sign the battery is the problem if the HV fan was running while I was driving when it all happened?

Would the lights go off on their own if the problem was fixed or would we have to reset them ourselves? I turned on the car today after it sitting for a day in the garage and the red light is still on.

 

If the hv fan in the rear passenger side is on, it's most likely you have a hv battery failure. Once the problem is fixed, the lights will go off on their own, you don't have to reset it (it's usually several lights that stay on 3+)

 

Do you all have any tutorial recommendations for changing an hv battery? It'll be my first time.

I'll see if I can get a reading on the codes.

Is buying a new oem hv from Toyota as simple as swapping the packs or it more complex?

The way I'm understanding it is with a new hv from Toyota I'm getting a whole new pack. With 2k1Toaster I get the modules (which I still don't completely understand) and I swap those out.

Trying to puzzle the pieces together before I get my hands dirty.

 

Buying a new pack from Toyota, you'll have to switch over the ECU portion of the battery pack to the new battery (this all comes out together in 1 unit and bolts back onto the new battery). The old battery portion will be returned back to Toyota for your "core" refund ($1350).

The 2k1 pack are only battery modules. You have to remove the battery modules from your old pack and put in the aftermarket modules from 2k1 (these modules are not the same as OEM, you only get 14 instead of 28 from factory (they are designed to be double the size)). This has the benefit of not having to return a core to the seller.

Swapping both will be quite straight forward, it's just a very heavy battery to be moving around. The OEM swap will be much easier and safer, you don't really have to mess with the individual batteries and touching the wrong parts to electrocute yourself.

 

That's good to hear. I'm looking forward to working on it and getting it back up.

Does anyone have any tutorial recommendations or instructions to go by?

 

There are instructional videos on Youtube for most of what you need done. Having many of these gen2 cars, I may recommend not buying a new battery that will last another 10 years. If you can source something that is about 5 years old for less, maybe that would be the best route.

As the gen2 cars age, many of the parts will start failing. The expensive parts being the brake actuator, catalytic converter (when they get stolen too), shocks/struts, bad wheel bearings, HV battery, and of course engine and transmission. Less expensive common failures would be inverter pump, leaking water pump, combination meter, etc. The failures of these parts usually will cost over $1000+ in repair costs and on an older car worth $3000, it's just very hard to invest in repairs in this price range.

I've nearly replaced all the parts I've mentioned on my 2005 in the past couple years and all of them were DIY projects. If I paid a mechanic to do all the work, it would be well north of $5000+ for a car that's worth less than $3000. Basically if you can DIY, you can get away with owning something past 13 years old. If you depend on mechanics to do the work, best you sell the car before these parts all begin to fail. Once you start, you won't be able to stop.

 

I am certainly not a DIYer, but I just thought I'd throw in here that I know someone, who posted about it on this website, who had warning lights about hybrid battery failure in a Gen 1. She did some research to try to figure out what to do, and in the meantime kept driving it as usual. She literally had zero problems with it for months and then finally decided to buy a Gen 3 and gave the Gen 1 to her sister, who kept driving it with no problems! So maybe option 4 is to do nothing and see what happens? :-D Cheapest option. I'll check with her and see what has become of the beloved Gen 1.

 

Here's her (@SmallLibrarian) original post with a lot of serious codes, just FYI:
This is my first time posting. I think that my car might be at the very end of its life but I thought I would try to confirm things before I start planning the funeral. (I will try to keep this short.)

I have had this car since 2013. I bought it off of Craigslist during my junior year of college. The guy that I purchased it from told me that he had recently purchased and put in a new hybrid battery.
I don't have the paperwork at the moment, but I know that I have put a lot of miles on this car since purchasing it. The car is at 220,000+ miles now. But everything seemed to be running as normal a couple of months ago when the third alert light (the one that is just a car with an exclamation point over it) turned on. It kept turning on and then going back off again, for longer and longer stretches of time.

I didn't have time to take it in for a bit, but when I finally did I thought it would be something that could be fixed by a lot of general maintenance and upkeep. No such luck. I was given the news that my best bet is finding a new car. The guy at the repair shop told me that the inverter cooling system has been malfunctioning, likely for some time, and that it has damaged the hybrid battery.
A diagnostic test came back with these codes (it's a lot of codes):
V2101
P0103
P0003
P0203
P0303
P0400
U2102
P03E1
P0101
P1455
P3191
P3000
P3101
P3130
P3009

So, as you can see, it is bad news bears. But my question is, how is it that my car has been functioning with little to no change this whole time while somehow also completely self destructing? I'm still driving it at the moment and there is no change in gas mileage, no change in how it sounds, no change to how the battery looks on the screen (I don't actually know if this changes). Maybe it's been dying for so long that I've gotten used to how it runs?

Thank you for any help or advice that you can give me! (Sorry if I missed any important info.)

 

Thankfully all went well in my DIY battery swap. I posted it about it here.

Financially it made sense for me to go with a new hv battery from Toyota. I wanted to the reliability of a new battery for another 1-2 years of drivability. Hopefully it all holds together @JC91006 .

Big thanks to @SFO for helping me find a great deal on a new battery from Toyota; 2k after core refund.

@Chodronish one thing that I learned while doing this DIY is that the hv battery has a bunch of modules. One of them could be faulty and that could be enough to trigger the codes. But it's possible to drive on it until it gives out. Maybe it's 10 minutes or months. Depends on the rest of the battery.

I believe this is how it works. Please correct me if I'm wrong.

To me it wasn't worth the risk and I wanted the peace of mind with fixing it.

 

@PriusFruit thanks for the info! I contacted @SmallLibrarian and found out this: "You know, that crazy thing is still running fine. My brother still has it and he and my dad did a bunch of routine tune up work on it (just changing some spark plugs and such) a few months ago and it is still running fine. The AC still goes in and out my brother said, but also he just drove the thing from Indiana to Maryland a couple of weeks ago and he did get a flat tire on the way home but that was because he ran over something. It's the craziest thing, I don't understand how it is still alive." This has been well over a year now.

 

Been a lurker for a while but I also have a 2005 Prius w/168k mi that I picked relatively cheap over a year ago that was in relatively clean condition with ALL service records from Toyota up until that mileage. I put 15k miles on it and finally last week it popped up with the red triangle of death (PA080) but it still drives fine. I picked up a new HV pack from my local Toyota dealer (approx. $2k) just this past weekend and swapped it myself.

As what @JC91006 stated, it's a bare pack and you will to swap over the vent tubing from the old back and install the new HV cabling. You need to pay attention when swapping over the relay/computer to make sure you don't mixup the nuts for new HV cabling as well as the ALS nut that holds down the black/metallic cable beside the ECU. The nuts are unique.

Ideally, you'll need a 1/4" torque wrench to tighten the bus bar nuts for the HV cabling to 48 in/lb. I made the mistake of not reinstalling the thin metal plate that goes on top of the HV frame cable when reattaching to the car since I wanted to test everything before closing up the casing. Car threw a bunch of codes (P0AA4,P0AA1,P3000,P3004) complaining the positive/negative battery contactor circuit was stuck closed. After fully reinstalling everything and clearing out all the codes with a bluedriver code reader, everything worked fine and there's no more errors.

I have a couple of other cars so this one is just a get around/beater ride. I figured if I wanted to sell the car I'd still be able to recoup my money since it's got a new/OEM HV pack with the latest modules. It isn't worth anything with a bad pack. Feel free to reach out if you decide to DIY and need help.

 

Nice work @adrian0115 and thanks for adding to the chat!