P0AA6 w 526 and 612 : I don't think it's the battery - what next?

Interesting. So if you set your normal DVOM to volts, you don't get any voltage reading at all between #13 stud and the battery case?

I can't tell from your pics, but I'm wondering what that dark half-circle is under the base of #13 (near where the mounting screw would be on the underside?). Don't know if that's a smoking gun or not...

And I probably would NOT use a megger while the battery ecu is plugged in- don't think it would like 500-1000V.

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The answer could be simpler. Your megger is showing a resistance there of 9.5 million ohms. What's the maximum resistance reading your Craftsman multimeter will display?

Even with the megger pushing 500 volts, the leakage current through a 9.5 MΩ resistance is only about 53 microamps.

With a regular multimeter, which is probably only using a few volts in the resistance mode, it would have to detect a resulting current down at some fraction of a microamp. That can be a tall order for a general-purpose meter.

Well, in the catalog, it's called "wire, frame, #2", the same way a catalog might list a "bearing, wheel", a "cover, valve", or the like.

When we take the commas out and aren't talking like Yoda, those are valve covers, wheel bearings, and number two frame wires.

 

The Prius itself does not just rely on detecting tiny current leaks to detect an isolation failure. On top of the battery's DC voltage, the battery ECU imposes a distinct, recognizable AC waveform that looks like something invented by Klingons. The manual, in a funny translation, calls it the "short wave". Not as in, you know, the radio band, but just a wave, that's used to check for shorts.



If the battery ECU can then detect any of that same AC waveform outside of the high-voltage wiring, you get the code.

Your zero reading is what's more surprising.

Yes, 0.4 to 0.7 Ω is too high for a couple feet of heavy wire. But normally, when you're testing something like that with a general-purpose ohmmeter, your reading ends up being more about your test leads and how clean the surfaces are where you put the probe tips, than it is about the resistance of the thing you meant to measure.

A milli- or micro-ohmmeter made for measuring such low resistances will have a four-wire connection, to make sure it can cancel out those lead and contact resistance effects.

 

They used to cost $60... Do you know anywhere they're still that low? I'm seeing up near $80 these days. I'm actually working with Professor Joe and some rebuilders to try to create and aftermarket version of these, as well as refurbished ECU because both of the parts are getting harder to find.

 

He said ships in 1-2days on website orders. Most battery folks use UPS for shipping and my experience is if you order early Tuesday you get it by Friday, but sometimes that turns into Monday.

 

$62

2009 Toyota Prius Parts - ToyotaPartsDeal.com

 

Toyota Parts Deal $75 after shipping and taxes.

Amayama $45 after shipping and taxes

 

I order them 10 at a time, which kind of dilutes the shipping cost, and have never had any problems getting them.

Shipping from Japan is $17 the UAE is only 10 bucks? That's impressive, but I've never ordered anything from yabbadabbado, is it reliable? 3 weeks? or is that typically accurate? Any personal experience with those delivery times?

 

Haha, speaking from personal experience? Yes I did order some plastic clips (half price including shipping compared to Canada) from UAE, currently there is no postal delivery from Japan to Canada. Yes took 3-4 weeks but I received the order. There is postal service Japan to USA, seems to be more cargo flights.

Gen 2 batteries $1300 from Amayama, but Amayama cannot obtain MSDS from Toyota to allow them to ship. DARN.

Email from Amayama
Japanese Customs does not allow flammable, high pressure or prohibited items such as batteries, airbags or gas generated seat belt pretensioners to be sent by any form of shipping from Japan without an MSDS document (data sheet from the manufacturer outlining safety procedures for the product) which the manufacturer has refused to provide to us, so I'm afraid we cannot supply it.

 

Welcome to the hell that is using toy remote control car battery chargers to repair non-toy real car hybrid batteries... In this use case, the less you rely on the "features" of your charger the better.

 

Yep, that's what I was referring to that @TMR-JWAP says is no big deal and you can do this with cheap equipment. Of course he's more determined than most, so gets better results.

As for how I do it: I usually charge them up till it reaches roughly 8.7volts... I also charge in stages to keep heat down. But once you have a rack of modules being charged with multiple chargers ( I'm up to seven total chargers and 7 total light bulb dischargers) it's easy to have some charge too long. I've found that the more in need of reconditioning a module is the faster and higher the charge goes. As in when I first start working on a bad pack, many modules will soar up past 9volts quickly, but after a third round of reconditioning it takes way too long and creates an uncomfortable amount of heat charging them back up to a full 8.7v, which of course quickly drops down from that number soon as you stop charging.

 

Now that I have 7 chargers and 7 dischargers the reconditioning is fairly efficient, but still takes a long time. But early on with far less gear took forever.

And don't worry too much about resting voltage balance too much, just get all the modules as fully charged as possible by charging multiple times to keep temps down. The voltage balance during a heavy charge or discharge in the car is where the lack of balance is the problem. And it's not that expensive to: Build Hybrid Battery Maintenance Gear For Under $100 | PriusChat

In general, it's quite the rabbit hole to go down... Some people just replace the bad module and luck out with as much as a year with no further hassles.

Obviously because it's your daughter's car, you're gonna wanna make sure she has an OBD2 in the glove box and has Dr. Prius app on her phone so ya'll can monitor the pack's vital signs and clear error codes so she doesn't get stuck on the side of the road.

As for additional diagnostic work you may want to do on the pack, here's a list of how many things you can try starting with your requested test for lower capacity:

--Record voltage drop at the 2 minute mark with a 12v, 50w bulb (Halogen bulb from Prius Headlight is ideal) 0.2v to 0.4v is normal loss

--Test modules for voltage loss with higher amp loads for shorter period of time

--Use thermal camera to detect cells running hot because they'll fail sooner than ones that don't

--Weigh each module on a scale and eliminate the lightest ones (hydration/venting damage)

--Record voltage loss of each module 3 days or longer after full charge & balance (self discharge test)

--Monitor voltage discharge during reconditioning for modules that fall off a cliff faster than other (symptoms improve w/each conditioning round)