Important - Gen3 Taxi Drivers, Dog Owners Or High Use Owners

[Grumpy Cabbie]

There have been a number of reports of premature HV Battery failure in Gen3/2009 onwards Prius. The use of the word premature is used loosly as the failures are in high mileage vehicles that have covered over 80k miles or so (which in 2 years is going some). However, failure of the HV Battery at 80k+ miles is a serious shortcoming, especially as the gen2 Prius was regarded as being able to achieve 500k+ miles. (The cynic in me believes this might be why Toyota initially limited the HV warranty on the gen3 to 60k miles!?!)

Well, if you're a high use owner such as a taxi driver then there appears to be a problem with dust or lint blocking the HV Battery cooling fan redering it useless and thus overheating the HV battery causing failure. This problem can also apply to lower mileage dog owners who allow their dog(s) to occupy the rear seat near the fan vent.

Toyota USA have become aware of this issue (their warranty being 150,000 miles in many States) probably due to replacement of expensive HV batteries under warranty, and as such have issued the following TSB Toyota Service Bulletin requiring the HV fan is cleaned every 25,000 miles for high use vehicles!

So, to cut the waffle, if you use your Prius as a taxi or carry dogs on the rear seats then print the attached TSB out and hand it to your dealer next time you pop in for service.

T-SB-0198-11.pdf

[dervdave]

There have been a number of reports of premature HV battery failure in Gen3/2009 onwards Prius. The use of the word premature is used loosly as the failures are in high mileage vehicles that have covered over 80k miles or so (which in 2 years is going some). However, failure of the HV battery at 80k+ miles is a serious shortcoming, especially as the gen2 Prius was regarded as being able to achieve 500k+ miles. (The cynic in me believes this might be why Toyota initially limited the HV warranty on the gen3 to 60k miles!?!) Well, if you're a high use owner such as a taxi driver then there appears to be a problem with dust or lint blocking the HV battery cooling fan redering it useless and thus overheating the HV battery causing failure. and as such have issued the following TSB Toyota Service Bulletin requiring the HV fan is cleaned every 25,000 miles for high use vehicles!

How did yours look, was it blocked ? :o

[Red diesel]

Damn - i was thinking that the Prius was the chap to deliver relatively hassle free motoring rather than silly modern diesels with DPFs and

silly small petrols with stupidly high out puts for a very small size (1.0 engine producing 123 bhp - sorry but no thanks - i don't want to

have to scrap or face a 10 grand engine replacement bill every 80 000 miles)

However on a slightly more positive note - if cleaning the fan prevents the problem - then its not necessarly a big issue - once owners get it done.

If its not too dear to do - it could even be incorporated into normal servicing, how hard is it to get at this fan - is it easily changed

Red diesel

[valmiki]

Interesting...I'll be checking this out when I take delivery of my 2009 (59) Prius 40k mileage in a couple of weeks...

Is there such a thing as a Prius Service Manual available over here?

[Grumpy Cabbie]

If you care to look at the TSB link you will note it only applies to vehicles used over 15 hours a day, used 6 days a week and the rear seat (where the HV fan vent is) is used 50 times a day.

If ALL 3 of those apply then the vehicle needs the fan looking at. Hardly means the Prius is not cheap and hassle free. Diesels are far from perfect too. I know of many diesel cars that have issues in taxi use where manufacturers have bought the cars back as they're not fit for use. OK if this service recommendation isn't followed, it can cause premature failure of the HV Battery. Again, if certain recommendations on diesels aren't followed, then they too can suffer from premature failure of expensive items - dpf's every 25k miles is springing to mind.

I'll be getting my HV fan checked at the 70k service. It's easy to DIY it as it's only a few bolts to remove the panels but I don't fancy messing about anywhere near the HV Battery. :)

One thing I have noted is that Toyota don't recommend installing a filter over the air vent as some diy-ers on the US forums have done. Perhaps this restricts air flow too much, whereas cleaning the fan every 25k miles solves the issue??

[suemonsalve]

I am the owner of a Prius taxi in Spain and had to replace the Battery at 179.000kms. Toyota does not want to pay for the replacement even when the cleaning of the cooling fan was not recommended nor done in the maintenance service for severe use. I have downloaded the Toyota US recommendation for legal procedure. Many thanks.