car stopped running, 4 codes pulled

Multiple pricey problems changes the situation significantly.

 

$700 for a transmission install? That's a deal. I would take him up on it!

Even if you simply sell the car afterwards, the $700 will be offset by the increase in the sale price compared to a non-running vehicle.

 

Also JC91006, you shouldn't just assume that the traction battery will self destruct or something at a given age or a given mileage (like 10 years or 150000 miles for example). The best predictor of a battery's future state of health is its current state of health, not its age, and not its mileage either.

 

I agree that the traction battery's ultimate service life cannot be easily quantified, as there appears to be a very wide range of actual outcomes.

However I do not understand how uart would translate "current state of health" to a prediction of future state of health. There typically are no advance warnings given when the traction battery ECU decides to log a DTC. One day the Prius is working fine, the next the dashboard looks like a Christmas tree and driveability is significantly impaired.

In any event, I think that 2G traction battery failure is not a big deal for owners who can provide DIY labor on the replacement and can source a battery from a salvage yard, etc. This is primarily a big deal for owners who have to depend on Toyota dealer service and installation of new parts.

 

Let me explain what I mean. If you were really worried about the likely remaining longevity of your traction battery, then I say the best thing is to actually look at the module voltages, amp hours and internal resistance. There are a lot of devices/software that can do that these days, including now a relatively cheap "stand alone" obd2 device. That info is a way better predictor of remaining longevity than either age or mileage.

 

The problem is that you don't know the underlying numbers (population) to deduce any reliable statistics from that anecdotal data.

What is the failure rate per year for batteries at around 150k miles. Is it 1 in 10 (per year), 1 in 100, 1 in 1000 - you tell me. With all of your anecdotal data can you even tell me to the nearest factor of 10 what are the true underlying statistics?

 

An excellent question. I certainly can understand and appreciate the thinking of an owner who decided to perform a preventive replacement of the traction battery due to age and mileage.

The 2004 currently has 165K miles and is 10 years old. The car is our daily driver and logs ~25K miles per year due to frequent road trips.

For fun and so that I can eventually post in the 200K mile owners sticky thread, my wife and I have decided that we will try to log at least 200K miles on the 2004 before letting it go. That will be the most miles we have logged on any vehicle.

I have thought about whether I should do a preventive replacement of the 2004's traction battery. The 2001 Prius and 2006 HiHy both had their traction batteries replaced under warranty, so I have first-hand experience regarding traction battery failures.

I decided that I will accept the risk of seeing whether the 2004's original equipment traction battery will last during our ownership period. However I carry tools in the car so that I can disconnect the 12V battery if necessary.

That will enable me to deal with high voltage ground fault issues and minor battery module imbalance issues, simply by clearing the DTC temporarily. The car will function until the DTC is logged again and the car turned off. Depending upon the DTC, the hybrid vehicle ECU may not allow the car to become READY again - hence requiring this workaround.

Hopefully the workaround will give me sufficient limp home range so I can get the 2004 home if necessary. If not, then I'll get to pay big bucks for an emergency traction battery replacement out in the middle of nowhere...

 

As a matter of fact, we do have the AAA family membership with extended towing... Thanks for the suggestion!

 

Did you check the 12 v battery voltage? When the 12 v battery dies, you get all kinds of weird codes that all go away when it has enough juice. Look on priuschat how to check 12 v battery voltage.

 

Old Priuses seem to have a design flaw, where a part of the motor generator 2 is located in a place where oil can't reach it, overtime it burns and the motor won't work the way it was designed to work, and later on it will fail.