2008 and the P0AA6 Code

We collaborate with other organizations doing similar work in other regions. We have received more P0AA6 than other regions by a factor of 4.  The problem is MUCH more common on the 2008 model year accounting for 80% of them.

We have concluded that a manufacturing defect for the 2008 model year exists where some have a tendency to leak more often than others in the harsh Phoenix heat.

One of our few warranty claims has come from a pack that was taken out of service for a P0AA6 code.  The offending module was replaced, and the pack was reconditioned with other replacements made due to performance.  This pack tested exceptionally well and was installed in a new customer's car. The pack performed fine for 5 months until it triggered a P0AA6.

Subsequent to that failure, we took in another 2008 pack with a P0AA6. After testing, the pack developed 4 more leaking modules.

This business only works because we are able to take customer failed core batteries, recondition them and supply them to future customers.  We have made a decision to NOT put 2008 P0AA6 packs back into circulation. As a result, if you have a 2008 with a P0AA6, your pack will be disposed of, and you will be charged a $600 core fee. We will still collect your battery in order to take it out of circulation. It will be turned into Toyota for recycling.

Simply put, if a customer core battery is not usable for future customers, we take a complete loss on the installation of a reconditioned pack.  This happens from time to time and is the nature of the business. While that can't be predicted, a P0AA6 leak on a 2008 can - it's a death sentence for a pack. We don't have a magical source for packs. If you've looked around, packs from salvage yards cost about $1000.  That's about what we pay for the packs we use as sources for modules we replace in the reconditioning process.

Should you choose to purchase a NEW battery, there will be no core charge as it's going straight to Toyota.

We apologize for this inconvenience.

 

I have the red triangle, and my car won't start

There are only a handful of codes that will prevent you from starting your car.  The most common is a P0AA6 - HV Leak.  This means that some part of the insulation between the high voltage system is "leaking" voltage to car ground (chassis). It is typically in:

  • Battery
  • Harness
  • Transaxle
  • Inverter
  • A/C compressor

Unfortunately, unless you have a code reader on-site, getting codes read on a Prius that won't move is impossible.  Your best solution is to disconnect the 12V battery to clear the codes as follows:

  1. Remove the mat
  2. Remove the cargo tray cover
  3. Remove black plastic cargo tray
  4. Remove cover over 12V battery in the passenger rear corner
  5. Remove purple (maroon?) plastic covering battery terminal.
  6. Disconnect the center of the three connectors.
  7. Leave it disconnected for 2 minutes - don't close the hatch!
  8. Reconnect it.
  9. Replace black tray, cover and mat, but leave the covers that had been on the 12V off for access - this way you can just open the hatch and disconnect the 12V if needed.

This first minute of this video shows steps 1-4 above.

https://www.youtube.com/watch?v=6fsX4ODT5OA

For step 5:

For step 6, user your finger to hook the underside of it, remove this plug:

After connecting the 12V, you may attempt to get the car in ready mode; however, it's a little finicky after the 12V has been disconnected.  Do it as you usually would, but you may need to press it 2-3 times about a second apart.

This will allow you to start and drive the car 99% of the time. If you don't succeed on the first try, and the warning light returns immediately, please try 2-3 more times ensuring you are leaving it DISconnected for at least 2 minutes, as it really is 99% successful. The #1 mistake is not leaving the 12V disconnected long enough. The #2 mistake is not pressing the ON button 2-3 times, 1 time/second until the car goes ready.

Once you are able to get the car started, drive it normally until the light comes on. Once the light comes on, drive STRAIGHT to O'ReillyDO NOT TURN THE CAR OFF.  Keep the car in ready mode and ask them to check the codes for you.  Get the CODE(S).  Don't let them tell you the description. I recommend O'Reilly because they use Bosch code readers that are usually very successful in reading codes that others won't.

If it's a P0AA6, you can continue to drive the car that way by disconnecting the 12V and reconnecting. It's a hassle, but it's the difference between being inoperative and mobile. Toyota disabled the car for a reason, so there is a legitimate safety concern, but I would personally never choose being stranded over being able to return home or to the shop.

A recent customer drove his car for several weeks before correctly diagnosing the code and coming to see me.  He used a hand-held OBDII reader to clear codes rather than resetting the 12V above.

It is important to diagnose the issue in short order.  As noted above P0AA6 can be triggered by many causes. Typically only the dealer (or Phoenix Hybrid Batteries) can read the sub-codes that point to the different potential causes.

The dealer typically charges more than their normal fee for this code due to the far more involved diagnostic process. I can either exclude or confirm that it's in the battery in about 5 minutes.

 

My battery is BARELY out of warranty. Why won't Toyota cover it?

Well, if the dealer is telling you that, it's because they likely make a little less money on a warranty and aren't motivated to go out of their way to help you.  That is not fact.  It's speculation on my part.  What does seem factual is that MOST dealers or at least the first-contact service people aren't interested in providing value for the customer.

As much as I enjoy reconditioning batteries and providing value for customers, I can't sit here and tell you my reconditions are as good as a brand-spanking new battery from Toyota. To that end, a new battery... under warranty or a "goodwill warranty" from Toyota may be your best value.

If your car is only slightly out of the 8 year/100,000 mile warranty in AZ, then you might get some consideration from Toyota Corporate, particularly if you are the original owner and are only over one of the criteria.  Still inside 8 years, but only 105K miles?  Only 4 months out of warranty, but 90K miles?  A little out on both?

It's worth a call!

800-331-4331, option 4

Things that will work to your advantage:

  1. Original owner
  2. Car has had other problems that haven't been covered
  3. "We are a Toyota family"

Be polite, be respectful, but be insistent.  I have had two potential customers get new batteries for less than $1500.  Well, technically, they aren't my customers, but I helped them get the best value available to them. :)

EDIT:  Yet another!  You can read his account in our Google Reviews!

Do You Work on Other Hybrids?

Here at Phoenix Hybrid Batteries, we have five hybrids.  It runs in our blood.  In addition to the Gen2 Prius, we have a Gen1 running a conversion pack (Gen2 modules installed), a 2nd Generation Honda Civic Hybrid and two of the 1st generation Honda Insights.

While Our principal focus is the 2004-2009 Toyota Prius, we can also work on other models.

TOYOTA CAMRY

We do not stock 2007-2009 Camry packs, and the few we've evaluated have shown substantial deterioration. It appears the Camry is VERY hard on its battery, and reconditioning at the higher mileages is a losing proposition. We can provide you with options including a new pack for FAR less than the dealer charges.  If you locate a battery, we will install it for $200.

NISSAN ALTIMA

We do not work on Altima packs. They are essentially the same as a Camry pack, and they are just as hard on them. They eat them. We had the opportunity to test one, and it was severely degraded with essentially no response to reconditioning. We can't offer new packs either because Nissan is incredibly proud of their packs (made by Toyota).  If you locate a battery, we will install it for $200.

Lexus GS 450h

This is a tough one. The GS 450h has an overheating problem.  If your pack has been replaced and the HV ECU updated, then there should be no issue.  If your HV ECU has not been updated and you get the overheat code, P0A7F, your battery is cooked, and rebuilding or reconditioning is not an option as your pack is effectively destroyed. The modules have been damaged by the heat, and they are only suitable for recycling.

We can conduct an in-depth evaluation.  Due to the time and labor involved, there is a non-refundable charge of $400.  This entails making an assessment of all 40 modules in your pack.  IF we determine that we can rebuild your pack, the $400 is applied towards the cost of reconditioning, and you only pay the price below. If your core is not recoverable, we will not be able to help you.

If we determine we can rebuild your pack, we do not stock Lexus packs, but we can rebuild it with matched modules at our shop and install 2-3 days later for $2,200 with 12 month repair warranty.

HONDA CIVIC/INSIGHT

Unfortunately, reliable used sticks that perform well after reconditioning are in short supply for the Honda hybrid systems.  New sticks can be purchased from Chinese suppliers; however, they have different characteristics and don't function optimally when paired with original Honda sticks.  However, when a pack is built from all new Chinese made sticks with the proper Quality Control in place, they can perform better than the Honda sticks.

We install Bumblebee Batteries when it comes time to replace your Honda hybrid battery pack. We have complete confidence in their incoming quality testing, sorting and matching process.  It is second to none.  They build a high quality pack at a very reasonable price and stand behind their product. You can't go wrong with Bumblebee's 36 month warranty.

If you can tolerate their wait, Bumblebee is the only organization that builds quality reconditioned packs for a reasonable price with a 12 month warranty.

For marginal packs, we can install the Hybrid Automotive Prolong Reconditioning Package. We charge their retail price plus tax and a small installation fee, but you save on shipping. This will give you a tool to do your own battery maintenance.  The Honda hybrid community has been grid charging their Honda hybrid batteries for several years with great success.  However, there are no guarantees that this will work with your pack.

Note that any price or service referenced may change at any time without notice

 

Why did my battery fail?

The most common failure is extreme imbalance that eventually drives a cell to failure.  There are 168 individual cells in your Prius.  These are contained in 28 modules with six cells each.  They all respond slightly differently to use and age.  Eventually, they get out of sync with one another until they no longer function well together, and one or more cells fails catastrophically. 

Additionally, while a robust design, there is somewhat uneven cooling within the pack.  The modules in the middle that are surrounded by a large mass of modules on either side, tend to lose their capacity more quickly than the modules towards the ends of the packs.

Here at Phoenix Hybrid Batteries, we have developed a process that reconditions the individual modules and restores them to near optimal conditions.  We're not going to tell you some number like 90-95% of their new capacity because that is very misleading. Those numbers are achieved with very low currents when compared to what they see in the car. To ensure the best results, we use very high current in our testing - representative of the currents the modules experience in the car.  Brand new modules won't meet 90-95% of their new capacity in our tests. There are several other pass/fail criteria that determine if a module is suitable for use.  On most packs, we find that about 20-25% of the modules within the pack do not perform well with their pack-mates for a variety of reasons. This is not because they are bad, but it is because they are not well matched/balanced.

This disparity is why reconditioning a pack with simple module replacement has shorter lived results than a completely matched and balanced pack.  We utilize strict criteria to ensure all modules perform optimally with their pack-mates.