My lovely Prius (X reg in the UK - 2001 I think) which has not had a day's trouble is suddenly on its last wheels.

I had to take it in for its MOT test - went in fine, passed except for a change of break pads but as I drove it home, the car was dragging - as if being slowed by a dynamo. I put it down to new pads - maybe they had put them on the breaking system.
The next day my car completely lost power and then died. I had to get it up-lifted and taken back to the garage.

The garage put the car through its 'codes' and decided that the transmission had gone.
Now, putting on my Sherlock hat, doesn't it seem a wee bit strange that the car's transmission should go just as it's being tested at a garage?

Anyway, they ASSURE me they never touched the transmission and it's just bad luck. Price of new transmission - the cheapest we could find was £380 and that was a back-street price. The price of the mechanical job would have been £1300 not including parts. Just about the value of the car - and the mechanic said - if we replace these parts, your batteries may go next.

I've got the car home - it's starting but feels very drunk. I've not taken it out on the road.

TRUTHFUL PART - Actually, during rainy weather, I did often get the signal on the screen with the exclamation mark and other warnings, plus the car would run out of power. I simply had to stop the car and re-start and it was fine for the rest of the day.

OK, please put your hybrid brains together and give me all your best ideas! My husband's car is a petrol-munching lexus - I don't want to have to drive it!

 

Regarding your "Being Truthful" comment. Was that before you took it in for the checkup? If it states as it is now, I had a similar experience on my PT cruiser.
Sometimes ok, sometimes locked in 2nd gear. A major auto parts store read my codes and said bad engine computer, a major transmission shop said either transmission and/or engine computer. I researched the web and learned that there is also a transmission computer and indeed this was the problem. Estimates of 4,000++ on the high end, fixed for $237 in my drive.

 

Hi Sophie,

This sounds bad. How many miles? All your miles?
Can you call up the garage and get the codes? They are typically "Pxxxx" codes. We can compare them to the know list and give you some better ideas of what has failed.

Losing the battery is always a risk but let's concentrate on the transaxle.

One symptom we have found with failed transaxles is a hum that varies in frequency with the speed of the vehicle. If you slip into "N" while rolling the hum frequency does not change except as the speed changes. But we really need the codes to understand what the garage found.

We found the 2001-03 Prius transaxles have a history of failures. We've been advising folks to change their transaxle oil at least every 30,000 miles. The Toyota interval is 60,000 miles but this is too long.

What we've seen in the past is a short develops in a stator coil. Thereafter the rotor spinning couples with the short and takes power from the car and heats MG2. We've seen very high temperatures, +150C, which is associated with this failure mode.

Your garage may be able to take an oil sample and testing verify the diagnosis. But changing or repairing the transaxle is not trivial:
http://classic.artsautomotive.com/PriusMG2.htm

Bob Wilson

 

Thanks for all that -
to reply to your questions,
the starting up with the screen showing a warning started a few years ago (almost as soon as I had the car) and mainly in damp/cold weather. (I live in lovely Scotland). By the time I got it to the garage, of course, the engine and screen were better. The toyota mechanic scratched his head and sent me away again. (I guess they could have looked through my prius computer history to see what problem had been?)
My car has done about 75,000 miles. Forgive me, I could check by going outside but it's very cold out there!
The whine does sound familiar - like a bike dynamo that goes up and down with speed.
I could and should get the codes - then you'll have the whole picture. Darn it, I owe them money which will HAVE to change hands if I ring them!!
I wish I'd known about the transmission oil - I guess the car with its warning screen was trying to hint to me that something was not right - now I feel guilty - a bad mum!

 

If the whine stays even if you shift into "N," that pretty well confirms their diagnosis. Sorry, but that is how they work.

You are in good company. Florian Steper in Germany had a transaxle failure too. In his case, there was some help because he'd bought it used from a dealer and there was some sort of warranty to help cover the cost.

Bob Wilson

 

Oh dear.
I wonder if I can use it just going the three miles to the shops and back? I wonder how long and far it can go. I will have to take it for a test drive around the block.

Is there any re-sale value in the car? It has 4 shiny new break pads that cost me about £200! If I put it on ebay, I am in the North of Scotland which rates 9.5 on the inaccessibility scale and the buyer would have to tow the thing away (in a truck because apparently you can't pull it over 30 miles an hour!)

 

As long as you understand it won't get better, you can drive it until it stops running. I believe Florian drove a couple of months not realizing what was happening before it failed hard. Eventually the car will throw a code that says, "I can go no further."

The most likely fatal failure will be an "internal short" code also called a "leak to ground." That happens when a short or even a resistance to ground occurs and is treated by the car as a safety hazard. It isn't that much of a hazard but this is the right thing to do, stop the car from continuing. There is no telling when that might happen.

Now the following are possible mitigations strategies to maximize running in this state and they do not have a hard record. Usually folks report the problem after the fatal code. So take this advice with a grain of salt:

• minimize duration and speed of trips - the short is taking power from the spinning rotor. If you can keep the speed and duration of trips short, the heat build up will be slower and you may get a little further. But if you wanted it to fail right away, take a long distance, high speed trip.
• change transaxle oil (have a sample, ~500 ml. saved in a clean, dry water bottle) - the by-products of excessive heat are likely to be found in the oil. Changing it now does NOT fix the problem but removes the accumulated material in the oil so it does not contribute to the eventual short.

Resale value is a funny thing. I suspect most used car dealers and buyers are the same so rather than reverting to some early Anglo-Saxton terms, let's just say ... "good luck!"

Bob Wilson

 

I am not convinced that the transaxle has failed based on these reports. Getting the codes will be extremely important. There are other failure modes (not uncommon) that are consistent with what you've reported. So please get the codes. Bob W also asked to take a 500 ml sample of the transaxle fluid. This could be informative but I'm not sure where you can send it (domestically) after the sample has been taken.

DAS