Codes P3000 and P3009 with Hybrid Warning Light

This is consistent with electrolyte leak that causes a ground fault. High humidity an cause the path to become more conductive. But I would also wonder about the module balance. But in the world of problems, this is one I would plan on by monitoring:

• min/max module voltages - looking for a greater than 0.3 V difference
• min/max module ID - looking to see if it has fixed on one weak module or still varies
• four temperatures - looking for a hot area, 3C or greater

Then start looking at different different pack options:

1. Toyota - obvious choice, still older modules
2. Rebuilder - ReInVolt and may be others, look for a warranty
3. Rebuild it yourself - study technical aspects and if you have place to do the work and time
   1. minimal - remove battery, measure voltages, remove and clean bus bars, identify leaking terminals, clean electrolyte, reassemble, and reinstall . . . wait for next failure
   2. modest - attempt to replace failing modules, same as above but use old-style replacement modules
   3. full - get 38, NHW20 modules, measure capacity and match charge

GOOD LUCK!
Bob Wilson

 

Also note that if DTC P3009 is the major issue, you can continue to drive the car indefinitely without implementing any repair.

 

Im sure they could, but if you are somewhat handy and have a friend, why not save the labor costs and do the swap yourself?

 

Don't take the dealers word that 3009 means Hybrid battery is bad. I've had customers spend $4000+ at dealer for new battery then have dealer tell them "sorry, your car also needs a new transaxle". Ideally you can find a good independent shop that knows Gen1's and they can properly diagnosis the car for you. Best thing to do is have tech unhook the "big orange wires" from MG2 and MG2 inside the invertor and "megg them out". If they don't know what "megg them out" means take the car somewhere else.

 

Run this simple set of tests to narrow down exactly where the code is coming from.

Prius P3009 High voltage leak code - AutoPro Workshop Blog post - Where Professionals Gather for Better Business

 

How is it you're in LA and didn't call me? The symptoms you are describing are more like this link. There is a good chance you can squeeze some more life out of your battery. I have fixed these before. Feel free to give me a call.

 

I'm curious how you resolved your issue because I've gotten the exact same error codes for my 2002 Prius. Let me know what worked. Thanks!

 

Patrick - are you saying that with the P3009 code appearing that no repair is necessary? toyota is telling me I need a new HV battery. Car starts and drives fine except for the warning light. It is in the Toyota shop awaiting battery replacement. If I do not replace HV battery won't the "display of lights" comtinue? As far as I know the lights still come on when the car is started. But it starts and seems to drive fine. Thanks for any added comments or suggestions. The work to replace battery is scheduled to take place soon.

 

Zoe, your own observation is that the car can be driven without a problem. Therefore I suggest you should be slow to take action given the $3,000 repair bill and the low market value of a 2002 Prius... It doesn't make sense to put so much repair money into a car whose market value is so low.

DTC P3009 points to a safety issue, where one side of the traction battery has a high voltage ground fault. This is typically because electrolyte from a battery module is leaking to the metal traction battery case, providing a path for the high voltage to leak to ground.

If you are willing to ignore the ground fault, you can continue to drive the car without replacing the battery at this time. The leak may get worse over time and you may eventually have to replace the battery, but at least you can defer the repair for now.

The trade off is accepting the ground fault safety issue vs. paying the four-digit repair bill. You'll need to decide what makes sense to you.

Although Classic Prius with this problem can be driven, 2G Prius with the same problem have logic that prevents the car from being restarted after the DTC is logged. Hence some owners have decided to disconnect and reconnect the 12V battery before each start, to clear the logged DTC from the traction battery ECU. Obviously they also are bearing the risk of the high voltage ground fault.

 

Hi Zoe,

Perhaps you might let us know the City and State you live in. There are independent Prius shops who can give a second opinion and handle alternative solutions across the country from coast-to-coast and North to South. Knowing where you live makes it easy to identify known, credible, independent shops. For example, these folks offer hybrid vehicle training and can recommend some of the folks they have trained:
Independent Hybrid/EV Repair & Service Shop Locator

Now many of us can handle our own maintenance so we're not limited to the Toyota dealer. Our own labor and we find these cars fascinating, working on them is not a big deal. It is a hobby as well as transportation. But for someone non-technical, like my wife of 35 years, self-maintenance is not an option.

BTW, a Prius-aware scanner is key to being an informed owner. It allows you to see the health of not only the traction battery but other subsystems in the car. It is a way to make an informed decision.

Bob Wilson

 

I was surprised to notice last night there's an actual impedance figure in the manual. Not sure why that surprised me, guess it just hadn't jumped off the page at me before, but there it is on p. DI-331 (2001 edition). Seems the threshold to trigger a P3009 is a path to ground of 100 kΩ or less. (Of course, that could also be the aggregate of two or more different paths.)

Using a digital meter with typical impedance 100 times as high, I wonder how practical it could be to just measure the case voltage relative to both ends of the battery and get a pretty good guess which module to look at, if only one has the uncorrected 'deep' leak. More complicated if you assume n modules might be involved, but for lowish n there might still be a practical technique involving more than two measurements.

-Chap

 

The relays might be open. It might be interesting to check the Orange safety plug contacts too. Just wondering if they might be hot or whether they may also be relay protected?

Bob Wilson

 

I was picturing the test with the cover off, so you'd have access inside at the system main relay. Yes, it would ordinarily be open and prevent you doing such a test from outside. The safety plug isn't on a relay; each contact will give you a connection to the middle module of one half of the battery. You could measure voltage from case to one of those contacts and narrow your search to half the battery. The system main relay again would prevent direct measurement at the other end of the half-stack, but still you could measure case-to-safety-plug voltage and divide by 7.2 to get a pretty good idea where the culprit is.

In the case of plural culprits it wouldn't be so simple. I haven't sat down to think clearly about it yet, but it might be if you had the cover off and made multiple measurements you could get a system of equations to solve. I'm also thinking that the simple case of one culprit at a time must be common, because as soon as you have more than one you'll have a circuit, with charge loss and heating and probably more symptoms than just a P3009.

-Chap

 

Thank you, Bob. The day the warning lights went on it was over 90 degrees and humid. No problems with weather before or after as it is generally mild, even cool, where I am, mostly in the mid 70s through summer. I have called Toyota with suggestions to try (from this board) prior to installing the new HV battery, but no calls back. Hopefully they are trying some of the simple things first to see if the problem resolves. I was told the Prius tech is "looking at it further" yesterday. Thanks again.

 

... where I wrote "middle module of one half of the battery" ... of course I meant the module at one end of that half ... just the end that's in the middle of the case ... if that makes it all clearer.

-Chap