2002: Verdict: transaxle and inverter dead

if you have not even heard the casue of the actual problem from the delaership, why are you scaring people with the 'electric motor died'
headline

there are probably other casues to the symptons you describe

 

well, not much we can do till you find out the diagnostic codes. report back when they call back.

 

<div class='quotetop'>QUOTE(canadiandriver @ Oct 10 2007, 11:10 PM) [snapback]523991[/snapback]</div>

First of all thats some excellent mileage you have there. Has the car been exceptionally maintained? Nothing about your post scared me though except the previous posts spelling.I was marveling at all the miles you've enjoyed. I wonder though after all the original commotion how come you didn't get out of the car and do even a cursory examination under the bonnet? Did you have excellent oil level?....Smell anything burning under the hood?...how did the motor sound sitting there idling? was it happy? I was shocked that after the original triangle of death you complain that it wouldn't do more than 70 miles an hour. I'm a very new owner and know very little about this car except when you see the triangle of death pull over and check it out.But it does sound battery/elec motor related. How's the charge level been? More details please.

<div class='quotetop'>QUOTE(canadiandriver @ Oct 10 2007, 11:10 PM) [snapback]523991[/snapback]</div>

First of all thats some excellent mileage you have there. Has the car been exceptionally maintained? Nothing about your post scared me though except the previous posts spelling.I was marveling at all the miles you've enjoyed. I wonder though after all the original commotion how come you didn't get out of the car and do even a cursory examination under the bonnet? Did you have excellent oil level?....Smell anything burning under the hood?...how did the motor sound sitting there idling? was it happy? I was shocked that after the original triangle of death you complain that it wouldn't do more than 70 miles an hour. I'm a very new owner and know very little about this car except when you see the triangle of death pull over and check it out.But it does sound battery/elec motor related. How's the charge level been? More details please.

 

There are a few facts that may apply or not:
1) The Prius will shift to a fail safe mode that will allow driving in some cases if the fault is not a safety issue (e.g. Inverter above temperature setpoint)
2) If the problem involves damage or safety then the ready light goes away and the car will not go (e.g. Inverter Overtemperature Shutdown)

It sounds like the problem is something along the lines of inverter overtemp, but this is just speculation based on a condensed description of the problem. There can be quite a few different failure mechanisms that could give similar results.

edit after seeing latest post:

I would find out the cost of just an inverter replacement. The DTCs did not state a transaxle failure, but I bet that the manual indicated that the transaxle 'could' have failed....so the dealer should be real clear as to why you have to spend all these $$$ for a new transaxle. Also post the DTCs. Many here can tell you exactly what the manual states for each DTC. [e.g. Why not replace the engine since a misfire was reported?]

 

Hi FL.. and Can....

The engine misfire could be related to the inverter failure. If the inverter could not turn the engine over due to a MG1 short, or MG2 short with MG1/MG2 missyncronisation, the engine would not start when expected, which the computer probably would record as a mis-fire.

It seems to me you probably did in the inverter in that last bit of driving there. Inverters do not like shorts, or opens. I had one industrial control go off like a shot-gun once due to being mis-wired. The Prius is a little less dramatic apparently, due to the on-chip temp sensors. But still, best thing is get into a safe location and shut it down.

 

Canadian, you might consider atacking this in stages:

1) The first post suggests that you exhausted the 12 volt battery on the roadside. Prius has some history of reporting irrelevant codes when the 12 volt system is low. May or may not matter in this case.

2) Classic Prius inverter assemblies from salvage dismantlers are rather common on ebay in the $USD 500 range. You might start by replacing just that, and not yet the transaxle. There is also an electrical coolant pump on that loop that should be replaced. When replacing the coolant (as always) pay particular attention to bleeding air and insuring proper coolant flow.

3) You could take a sample of the transaxle fluid and see what debris is present in its sump, as a physical test of whether things are damaged inside. There is a small library of other such fluid analyses, and if yours turns out very different, that certainly agrees with the diagnosis thus far.

4) Trying everything I can think of to avoid replacing the transaxle, because at the prices you mention, it is certainly the deal breaker.

5) If the car does end up being disposed for parts, the only options I know are to get a bid from a salvage dismantler, compare to sales prices of parts on ebay, and guess which would do you do you better in the long term. Eventually you could probably find buyers for the parts that commonly get banged up in wrecks, but I would not know if you want to dismantle the vehicle yourself. Every chunk of the car has inherent value, but only when you have a ready buyer for it.

Sorry I haven't any better news. Please keep us up to date on developments.

 

<div class='quotetop'>QUOTE(canadiandriver @ Oct 10 2007, 10:10 PM) [snapback]523991[/snapback]</div>

Was the frequency of the hum proportional to the vehicle speed or associated with the engine rpm?

Our transaxles have a unique failure mode when a coil on the stator shorts. Once this happens, the coil absorbs energy from any rotor motion causing the coil to get hotter and hotter. This shorts more and more of the coil and eventually it looks like this (if the image link remains


Thanks to Florian Steiper for his photo album. Florian's photo album shows what happens when a transaxle fails.

If the frequency was proportional to the vehicle speed, MG2 would have failed. If it seems more random or somewhat linked to ICE rpm, then it would have been MG1.

The inverter would be at risk because the shorted coil would look like a resistor, not a coil with an inductive reactance. Whether or not it fails the inverter is an open question.

It may be possible for your dealer to test the resistance between all MG1 and MG2 power leads to identify which MG1 or MG2 stator failed. However, knowing doesn't fix. The transaxle would have to be rebuilt but the inverter might still work.

Replacing a failed transaxle with a salvage should be done only after the MG1/MG2 leads are tested to make sure they don't have a problem. Also, I would strongly recommend the salvage transaxle be throughly cleaned by having the unit flushed or better still, have it opened, inspected and cleaned including replacement of all seals.

Art's automotive has a great set of web pages covering transaxle rebuild.

Bob Wilson

 

Thanks Bob, I was just going to ask if anyone has checked it with a multi meter, I have seen countless failure codes that are pointing out a symptom rather than the problem. Codes aren't the end answer, they are a clue where to look.

I'd hate for anyone to spend money on a transaxle when something else is wrong.

 

aww.

maybe see what you can get from a salvage yard? parting a car is an extremely slow process and it's probably far easier to just get a lump sum from a yard.

maybe someone here wants it, i don't know. but best of luck to ya!

 

<div class='quotetop'>QUOTE(canadiandriver @ Oct 24 2007, 11:22 PM) [snapback]530037[/snapback]</div>

As the other posters suggest, check salvage yards. I see multiple of them listing '01-'03 transmissions with the electric motor for about $500 USD. I can't imagine shipping being more than $150 or so. For about $1000 labor included you can have your car rebuilt by an independent shop if the transmission is the only thing you need replaced...

Or sell the car. IMO $11K for a repair on a car that is not worth more than $10K at best in "perfect" condition is not an option to consider IMO... Even half that would make me think twice...

If the tranny oil hd not been changed previously or regularly, at your mileage I would expect it won't look good, including some metal. But that does not mean a failure immediately. I would take the car back, check and charge/replace the 12 V battery if it is discharged (use a temporary good battery from any vehicle for the test if you whish), check the fluid levels and replace the tranny fluid with dropping the pan, clear all codes (any $30 code scanner can do this for you), check your spark plugs and give it another try. That's about $60 and a few hours time to make sure. You should see any codes thrown yourself with the scanner and then you can decide what to do.

I can symphatize though - my Camry '00 with 120K miles on it had its reverse gear go out recently. It is still in my garage - with the tranny half-way removed, hopefully will finish it up in a week or two. Btw, that failure was the reason to buy a used '02 Prius myself...