Dead transmission at 88K miles

It's a pretty rare repair. Your best bet would be to buy a used transaxle and have that swapped in.

Per car-part.com you should be able to snag one for around $750.

 

Just as a matter of interest have you had any work done on the air con system in the last few weeks. If so was it at the dealers or an independent shop. This can be relevant.

John (Britprius)

 

Thanks for the reply. The reason I asked is because this is not unusual when the wrong oil has been used in the AC.

John (Britprius)

 

How would the wrong AC oil affect the transaxle?

 

It does not affect the transaxle but gives the HV battery isolation fault observed in the first post.

John (Britprius)

 

The diagnosis makes sense, and as previously stated, you should look into the feasibility and cost of installing a used transaxle from a salvage yard.

Regarding clearing the DTC, you can try disconnecting the negative battery cable where it bolts to the body for a few minutes. However if the high voltage fault is solid, then the DTC will come back and you still won't be able to drive the car.

 

Are the MG's classed as part of the hybrid system in the US if so they would fall under the 8 year 100,000 mile guaranty or the carb state "if Phoenix is in a CARB state" guaranty of 10 years 150,000 miles.

In the case of the 8year guarantee this may still be in force or just out it may be worth contacting Toyota to see if they will help.

If Phoenix is in a CARB state it is under guaranty.

John (Britprius)

 

I think we've found that the transaxle (and all of its components) are not covered by the hybrid system warranty.

 

I obviously take your word for this, but that does seem strange as MG' are required in the system to drive the car and charge the battery and as such are part of the system. In the UK/Europe the transaxle is part of the hybrid guaranty.

John (Britprius)

 

In the US the transaxle (and the MGs within) is covered under the 5 year/60K mile powertrain warranty, not the 8 year/100K mile hybrid system warranty.

 

What a getout!!!

John (Britprius)

 

Seems very strange for such a failure to happen. Has the ATF ever been replaced?

 

It can fail, but you would be in the extreme minority.

Toyota says the ATF fluid does not need to be replaced. Ever.
People on here suggest because of studies done on our dime sending out fluids for samples that you should replace it early to get the initial build shavings out (like 15K miles) and then every 30K after that. That is a conservative number. Changing every 60K is probably more "normal", but that initial clean is key.

Just make sure your AAA shop knows Prii. The transaxle is not your average Ford's tranny and it will be unhappy if treated as such. For instance putting the wrong fluid in can cause isolation faults like you are seeing because the OE ATF WS fluid is specially non-conductive and some/most are conductive. Doesn't matter in a normal transmission, but in the Prius the fluid goes around the electromagnetics and you will get winding shorts.

 

I seem to remember a post on PC where water had managed to enter the HV connector on the transmission causing this same problem.

Has the car been driven through a lot of water or had the underside cleaned?

Most MG faults are shorted windings rather than ground isolation faults. I would inspect the termination of the HV cables where they enter the transmission.

I have not delved into this area yet, is it a water proof plug? or are the cables terminated under a cover?

John (Britprius)

 

Looking up fault code P0AA6-526,613 This can also be an inverter converter fault.

Unless already done by the dealer, disconnecting and meggering the MG's should be the first step. They would need to be disconnected anyway if the transmission is proved to be faulty.

John (Britprius)

 

Meggering?