Oh no! Hybrid system warning light.

Prepare to spend $125 for the stealership to read stored codes. Or you can go to Advance Auto or Autozone and have them read the codes for you for free.

If it's the HV battery pack that triggered the codes you can tell this by viewing the MFD in the state of charge mode. If the SOC fluctuates from empty to full rapidly your pack has a shorted cell in one of the modules. With 245K miles that's very likely. The code for this is P0A80.

I hope you're lucky that this isn't it but it's very likely that you rolled a 7 this time.

 

I got the identical symptoms on my 2005 prius (almost 200000 miles),i bought a code reader from amazon and it seems a trash can't read any code from my prius, to pay close attention to this topic, thanks!

 

What's the condition and age of the 12 V battery?

Have you heard the cooling fan in the back seat coming on?

The $15 readers from Amazon (I keep one in each car) will only read industry standard emission system codes, little else. Some of the parts stores have better scanners and will help with some Prius codes, but maybe not all and they may miss something important. But it's a good place to start at least, for the price.

 

Hi: andrewclaus, I purchased another mini-vci reader for toyota, is in shipping, don't know if it works for prius 2? my prius' 12v battery replaced once 5 years ago, I doubt the 12v battery may cause those symptoms? and in order to access the traction battery, I already removed the bleeding pipe from the cooling fan for the HV battery， so I can see the fan is working when the car being started, post some pics of defect lights and fan status: another information is I checked every single module of HV battery, only one has 6.8v and all others 8V( the single 6.8V HV battery module is the root cause for those light? )
@PanchoVilla201 sorry for hogging your spot, maybe i should open an individual topic for my car's problem, but at the same time I hope my information can help you, since we got the same symptoms on same prius, thanks!

 

sounds like a bad cell in the hybrid battery.

 

Yes, it sounds like the hybrid battery has a bad module.

Also, five years is close to the limit for the 12 V battery.

The Mini VCI with Toyota Techstream should work for all Toyota, Lexus and Scion cars.

 

On the Prius, there are two things that need to be done when any of the check engine/warning lights turn on:
1. Have the codes read to determine what is the cause. The first place to have this done is a local auto parts store that will read generic OBD codes. However these won't reveal all of the problems as there are Toyota specific ECU codes. To read these, you need to either use a Mini Vci cable with a laptop with Techstream installed (less than $20 for the cable), another code reader that can read Toyota codes, or spend the money to have your local Toyota dealer or hybrid specialty shop read the codes.
2. Confirm the 12V battery isn't bad. A simple Google search will tell you what the voltages should be when the car is off, ACC-ON, and when in ready. If the 12V is bad the car occasionally throws strange codes, which is why this is important. This is rare, but should be considered.

Get your codes read and then Google them and you'll likely be able to figure out what's wrong. Or post back and the members here are great at helping! Best of luck.

A bad sensor or bad catalytic converter could cause the check engine light to turn on, but the car to drive normally. A bad module in the high voltage battery usually results in the car going into "limp mode" where it has significantly less power. At 245k, a failing hybrid battery is likely to happen soon in your future and should be planned for, however to me it sounds more like a problem in the emissions system as the oil change place found such a code. I'm not sure why other members are immediately pointing to a failed hybrid battery.

 

In post #5, the OP wrote this: "another information is I checked every single module of HV battery, only one has 6.8v and all others 8V."

 

Nope. You have to replace the module yourself (if you do it the right way) or hire someone to do it (not recommended). If you don't or can't do this a remanufactured or new OEM pack are other options.

 

Not the OP, it was Henry Tan.

 

Aha, missed that. Thank you.

 

You'll find out after the HV inverter electric water pump is replaced if all of the warning lights disappear. If so, fantastic.

There is a possibility that you're still covered under Toyota's extended warranty program for this. You should have gotten a letter from Toyota about this issue 5 years ago (but I don't know if the 2008 model year was included).

If not, $600 is a little high. The pump is about $150 so labor at $450 is enriching the mechanic a bit too much IMHO. It's not that difficult to do if you have the tools and time. Most mechanics don't replace the coolant either, they simply pinch off the hoses at each end.

 

Best way to check the battery is to take a voltmeter directly to the battery terminals.

 

thanks a lot! according to the useful information from PanchoVilla201 and the related inverter water pump check video

, i checked my prius' inverter water pump status, it looks the "wave" in reservoir is very weak, in face, I think it's not the real wave or turbulence drived by the water pump? maybe this "weak wave" just caused by the engine vibration？and the pump seems no running noise? please the experienced members to confirm if my inverter water pump is dead, thanks! there is my water pump check video posted on youtube:

 

The inverter water pump makes a high frequency noise when running. At least the one in my 05 Gen 2 did.

 

Looks like the pump is fine try to watch is with your engine shut. And AC shut( must be in ready mode of course) Then you have no vibrations and hou can maybe hear the pump.