Transmission Replacement for 07 Prius

Wow. This is news to me. The bit about "the transaxle assembly has been improved to address this condition" is particularly interesting.

 

so there is a X set off transaxle assembly that have a fault..

 

$5K is a very reasonable price for getting a new transaxle installed at a Toyota dealer. You might check with your independent transmission shop to see whether it is willing to install a used transaxle from a salvage vehicle; that might save you considerable $$$.

DTC P3009 means a high voltage leak. MG2 or MG1 has a voltage leak to ground. This can be verified by removing the inverter cables to the transaxle and using a megger to verify that less-than-infinite resistance exists from the terminals to ground.

 

First, Contact Toyota, they have given breaks to owners before in cases like these before.

Second, has the transmission fluid ever been drained and refilled in your son's Prius? When you have it repaired, please save a few ounces of the used ATF in a clean poly bottle so that it can be sent to a lab for testing. Some technically minded Prius owners have developed laboratory data suggesting that 2004+ Prius ATF (Type WS) be replaced every 60,000 miles to extend the life of the transmission.

JeffD

 

Did the owner ever replace the transmission fluid with something other than the correct Toyota fluid? Other fluids are not known to be compatible with the high-voltage windings over the long term.

One thing more annoying than replacing a transmission is replacing it twice. I'd use a dealer for this.

JeffD, I though those data indicated a need for earlier fluid replacement based on the presence of mechanical wear products? whereas this is apparently a presumably unrelated electrical problem.

 

Richard,

The metallic load that builds up in the ATF over time is a suspect here as the MG windings are exposed to the ATF. Some possibilities are:

1. A decrease in ATF electrical insulation properties.
2. A source of winding insulation wear.
3. Possible chemical interactions over time.

That's why I have put in new ATF twice (60k and 120k miles) so far in my 2004 Prius. The used ATF was quite loaded with metallic particles at 60k (perhaps a little earlier first ATF exchange is justified), but was much better at 120k (The gear teeth are smoother after break-in so fewer wear particles).

JeffD

 

what were the symptoms leading up to this problem? lights on the dash? strange noises? complete power failure?

 

Thanks for digging up the info. Glad that I got a 09 but only time will tell if the "improvement" really works or not.