Short in transmission total replacement required

The diagnosis seems reasonable. I understand you might feel that the transaxle should be covered by the hybrid system warranty. However the Toyota warranty language is clear that the transaxle is covered by the powertrain 5 year/60K mile warranty.

If you can find an independent who is willing to remove and install the transaxle, an option might be for you to buy a salvage part, probably for $1K or so. Try eBay Motors, for example. Good luck.

 

There is no conventional transmission in the Prius. Gearing is accomplished by splitting power between the direct mechanical path and the electrical path of MG1-MG2. The short is in one of the MGs, which is why you hear humming and the HV battery drains.

Your problem is a warranty case only if you are still within the 5 year/60K limit.

Tom

 

If you don't mind a little background on the car? How many miles on it and how was the transmission maintained? When was the last trans fluid replacement please?Thanks.

 

You don't give a location, but if you are near the SF Bay Area, Art's Automotive in Berkeley and Luscious Garage in SF are two independent repair facilties that may be willing to use a salvage transaxle to fix your car. Art's Automotive rebuilt one before, but due to the time involved, they said that they probably would not try a rebuild again.

Hybrid Specialists

Luscious Garage | Hybrid Specialists

 

It's a reasonable thought, but Toyota is very clear about what they consider the hybrid portion, and the transaxle is not.

Tom

 

I wonder if it got the wrong oil at some point in time. It has been said that could cause such a failure.

 

if its only the second occuarrence of the failure ever observed. maybe you can contat toyota about this and you maybe get some discount on the parts.
even if its nog under warranty its still is a special accurents

its a littke bit strange a transaxle is not a part of the hybrid portion but the electric motors are only in the transaxle because its a hybrid car and without it there would be no hybrid drivetrain
so the mgs make this a hybrid car and are a part of the hybrid/electric portion.
thats what i think
maybe go to court and fined out whats what.

edit
also the definition of a transaxle is that its between the wheels and the thing that powers the car in this case the ice and the 2 mg's
ice,mg's - transaxle - wheels

 

David may have noted the only hope here: if the transmission fluid was ever changed or if anything was ever added to it, and you have it analyzed, and it's the wrong fluid, and you can determine who did it, you might press them for replacement.

 

The repair manual suggests that the tech verify the wiring harness connections to the HV ECU and the inverter. Then, the Toyota diagnostic laptop will provide freeze frame data, and given certain readings the transaxle should be replaced. It's a good sign they were using a megger, as the repair manual also suggests the use of that tool. The diagnosis seems plausible.

 

The motors are AC induction motors, IIRC, which would necessitate computer control. If MG1 is freaking out, it could feasibly be the ECU or wiring harness causing multiple coils to energize out of sync.

I bet the ECU isn't cheap, but I think it's arguably part of the hybrid system.

 

Hmmmm. Maybe check that the resolver cable hasn't been damaged
by that little metal plate underneath, which gives all the
vital position information back to the ECU.
.
Then they should start scoping GUU/GVU/GWU possibly through a low-pass
filter and make sure the ECU is sending proper 3-phase modulation...
.
_H*

 

Well, the components that potentially might be damaged would be the inverter and the hybrid vehicle ECU, and both are covered under the 8 year / 100K mile hybrid system warranty (or the longer CA warranty).

 

There is tsb's out for that code 04-05 my on both tsb's. I know yours is a 06. One calls for a inverter replacement the other calls for the replacement of the hv ecu. I have replaced inverters before for throwing out false codes, a bad solder joint was the issue on a prius and a highlander. I have replaced a transaxle on the 1st gens due to not being serviced it had a bearing roar and the fluid smelt electricaly burnt. The noise you talk about seems to be a low voltage issue. I can't remember which joint was bad in the inverter.