2008 Prius with new 12 V battery won't shift; lots of warning lights

When you say shudder is this a shudder at standstill?

 

this may be the longest repair thread ever.

 

No.

What happens is a short will occur in the stator windings. Thereafter, as the rotor turns, the shorted loop draws power and heats up. It draws power, much like a generator, on any motion and gets hot. This heat leads to further damage and increases the number of shorted, wire loops to draw more power when the car moves. The only fix is to replace the stator coils and this is ordinarily impractical ... not impossible but way too much time and effort for the result compared to swapping the transaxle.







Bob Wilson

 

So when you say shudder is this similar to a misfire shudder or something entirely different? A shudder caused by any movement with the MG wether it’s recharging, braking, accelerating, or cruising?

I wouldn’t bother replacing the winding on that either ha!

 

The one I experienced in someone else's car, the badly burnt one, was more of a rumbly hum. As the rotor spins, the drag varies by the relative angle and transmitted through the gears to the wheels.

Bob Wilson

 

Okay gotcha!

 

Let me simplify it


Posted via the PriusChat mobile app.

 

Shhhhhh!

Posted via the PriusChat mobile app.

 

Excellent data that confirms transaxle, MG2 is failing. In the meanwhile, AVOID HIGH SPEEDS! The amount of power drawn from the rotor is a function of speed and the clock is ticking. With gentle driving, you may have months before it fails hard. In contrast, the Prius with the blackened body easily reached 100C by the end of the block.

So let's look at the 'get well' options:

1. Independent Repair - knowing the transaxle is failing, there are rebuilders and quality Prius mechanics around but they may be hard to find. First on my list is: Prius hybrids sales and service Scottsburg Indiana, 812-752-5050. Steve has a business of buying 'salvage' Prius; stripping the working parts, and; selling what comes out with a warranty. He is about 321 miles away and with a backup plan, it would be OK to try and drive the car there. You know how to reset the 12V ground so driven gently (AVOID HIGH SPEEDS) the car could reach that distance. Alternatively, hire a U-haul flat bed trailer or dingy trailer and tow the car there. Another option is Taylor Automotive : Automotive Service and Maintenance in Sanford, NC, 919-774-4037 but Rex's shop is 555 miles away and has a lot of mountains along the way. If we route around the mountains, 582 miles. BTW, if over the phone it doesn't sound like a deal is in the works, ask if they could recommend anyone near North Alabama. Another resource, call or contact Automotive Career Development Center, 800-939-7909 / 508-852-5857, a hybrid training school and ask who they would recommend from their former students who are near Huntsville.
2. Do It Yourself - assuming you have an enclosed garage, coordinate getting a replacement transaxle and buying or rental of the unique tools. Study the YouTubes and every thread by others who have done this in the past including joining the Yahoo Group, "Prius Technical Stuff." Print hardcopy (or buy a used maintenance manual set via Ebay) of the transaxle swap. Coordinate a team (there should be two if nothing else for SAFETY). Schedule a date like a three day holiday, Thanksgiving, or Christmas/New Years to 'do it.' Even for novices, this is about two or three, long, hard days (the transaxle is heavy!) but it can be done. Day 1, remove the failed transaxle. Day 2, install the replacement. Day 3, figure out what we forgot and the party. On the replacement transaxle, inspect the transaxle oil to make sure it does not smell burnt. In time limited bursts of 3-8 hours, I can 'lend a wrench.' This should ONLY be used if there is curiosity about the car. It doesn't have to be a 'career change' but gaining understanding beyond what the usual owner might want. Motivation makes the job fun and we should enjoy what we do in life.
3. Sell a broken car - don't even think about 'parting out the car.' However, donating the car to a tech school is another option and becomes a charity deduction next year that is discounted by your tax bracket. But it may make sense to see if the tech school would consider repairing the car as a project. You might consider putting an ad in the usual places including the "nickel" publication that describes the car and problem to see if there are any takers.

Bob Wilson

 

For the Gen-1 Prius, there is an option of replacing the MG2 stator assembly. This YouTube describes part of the process:

It may be possible to do a similar repair on your car but notice it is a well equipped shop by the renown Lucious Garage. This has several distinct advantages including not having to remove the engine and transaxle from the car. But you still have to disassemble the driver side wheel assembly to gain access.

BTW, I disagree with Carolyn about the goal of replacing the transaxle oil. In my case, it was to reduce cold weather, rolling drag and later to get rid of early manufacturing debris. I don't think the oil induces the initial stator short. The problem is it is nearly impossible to identify the initial failure point as once the short develops, the internal arcing and heating does a 'bug zapper' on the root cause.

Google revealed there may be an independent, Prius shop: Huntsville Automotive Inc. | Auto Repair Huntsville, AL 35806 | Huntsville Auto Repair Shop & Service Center

I sent them an e-mail via their web page asking if they handle Gen-2 transaxle repair or replace. Some shops may have no interest. If they say yes, I think it makes sense to schedule an appointment and let them make an offer. They are near The Arc in an industrial park so I think it makes sense to at least ask.

Bob Wilson

 

Not saying you have not seen a no shudder blown trans but we have seen a Few of those.
But How do I have a dead shorted mg2 to ground and Have no drivability issues?
3 phase high power motors go nuts if they lose one phase. They shake very badly. The more power you give it the harsher it shakes,
That’s hard to understand. And how do I have intermittent failed windings that you can drive just fine on then
Weeks later throws a code?
The trans is particularly tough in this car and failed windings are very rare at least on this site.

But you fix them for a living I don’t so if you seen this before it’s probaby the trans. But there’s things Susie can do. Start checking things off the list.

Here’s what I would do.

I would call lusciousgargae in San Francisco and ask for Carolyn. She owns the joint and is very nice. I have talked to her before. Run it by her. Intermittent high volt leak no shudder no drive issues. I clear it and away I go.
Next suzie knows a hybrid battery guy. Ask him to take the battery cover off and take a lot of pics. I still suspect the battery even though it looks new. Clear pictures. Ask him to tighten up a few module nuts. Take a good look in there,

Then get a mechanic to drain and replace the trans fluid, but check very carefully and see if the fluid level is low in the check fill hole before dumping.. See if the fluid smells burnt.

My list costs about $300 all in. If negative on these start looking around for a used g2 trans. Last time I looked there was 6 on eBay.

 

Too comical. This thread reminds me of the horror slasher movies, where the next victim decides to stay instead of fleeing/calling police.

History of postings saying replace transaxle:

#87-pg5, #119-pg 6, #132-pg7,#202-pg11, #206-pg11, #238-pg12, #252-pg13
Only took an additional 165 postings (252-87=165), and 8 pages (13-5=8).
​

Since code P0AA6-526, has a list of things to rule out, but the two biggest culprits are HV Battery and transaxle. Since HV Battery was replaced with a new, genuine OEM, HV Battery, you are left with the remaining likely offender: transaxle. It is always possible that the new genuine OEM battery could have been defective, but probability is likely low to begin with, and that was not the case here. Vermin could have chewed on some wiring that could cause this code, but you would have seem evidence of chewing or have a undrivable car. An ECU could have gone bad, but they seem to have a very LOW failure rate here; bullet proof almost.

Unfortunately, you have to rely on paid labor, for a correct diagnosis, and to effect the correct repair. I get that, and can understand your concern of A will truly fix B, and not wanting to waste money.

Now you just need to find a competent person to install. OR you can become the next Carolyn Coquillette (Luscious Garage), of the South East. Remember, she did not come from a family of mechanics. Her part time job, during college, at a gas station got her interested. This is obviously a BIG leap, but anything is possible. Maybe you can hire Bob Wilson to help, or maybe he knows of a good mechanic.

Search "used Toyota parts," you will get a lot of results of auto dismantlers, near you; some will ship.

• From $604, 394 choices, lower mileage costs more; 2007 Toyota Prius Used Transmission - Auto Parts Fair®
• $270, 146K miles, Weller Auto Parts - Used Toyota Parts
• From $210, 44 pages of choices, PartsHotlines Used Cart Parts
• Call to see what transaxles available, Toyota Prius Used Parts
• From $292, 44 pages of choices, Part Search - 2007 TOYOTA PRIUS Transmission or Transaxle Assembly

 

If my trans went out I’d buy a new trans and $500 POS car. Use the POS for work and school while my gramps and I bond over alcohol and manual labor.

If he’s not down I’ve also got two or three other friends with garages and engine lifts!

As for Suzy it might be better to donate it for a tax deduction whether it’s for her business or her personal taxes (state the price you paid for the car). Then go car shopping with her daughter for either another Prius or something else. When I car shop I always check the vehicle myself, then have my mechanics check it out.

Alternatively she could send it off for a new tranny as mentioned before.

Either way you’re gonna be out money but in the end your daughter should have a great car!

 

Also worth mentioning that an independent shop probably won’t quote you close to $4k, my mechanic charged me $2k to pull the engine out of my Subaru, machine the head, new gaskets, water pump, clutch, and put it all back together with a two year warranty.

 

I went by Huntsville Automotive and they have what looks to be a good shop and clueful. I spoke with Pam who handles calls and scheduling. I am going in Thursday morning for a transaxle oil replacement, part of my transaxle oil study.

As for the 2008 Prius, of course they would prefer to confirm diagnosis and the rest is negotiable. I would ask about warranty if there is a problem with the replacement. That is about all I can do for the Gen-2 problem except to suggest printing out significant postings to share with them.

GOOD LUCK!
Bob Wilson

 

It occurs to me that a flooded car would have a perfectly fine transaxle. Both Texas and Florida have a large number of flooded Gen-2 Prius. This suggests there may be more Prius salvage parts available at lower prices.

Bob Wilson

 

The shaking is caused by the windings being shorted and likely having a different amount of resistance. While a burned and or shorted winding may also be shorted to ground, it can also not be shorted to ground. The code found in this car is for an isolation fault. This means the high voltage system is not isolated or insulated from the grounded portion of the car. The information code 526 basically means the short occurred while the whole system was online and can be anywhere.

I agree that failed windings are rare, but will add that failed inverters are more rare.

Maybe hearing it from Carolyn will make it stick? Anyways, why not drag her into this mess as well?

Posted via the PriusChat mobile app.