2004 Prius P0A72 Code

what are you reading them with?

 

to sure if that is giving you the correct codes. most here use mini vci.

 

I'd say you are looking in the wrong place.

P0A72 = Generator Phase V Current.

This would indicate the transaxle or inverter as candidates.

To be sure you need to take a 2 subscription ($15) at techinfo.toyota.com and look at the diagnostic troubleshooting tree for code P0A72.

BTW, your code reader is most likely adequate.

 

i stand corrected by dolj ^^^

 

It is not necessarily the inverter or the pump. That is why I recommend you look at the actual diagnostic troubleshooting tree, this will guide you through a logical process to find the most likely cause.

But if the inverter cooling pump is not performing that will need looking at too. However, this code doesn't point there. That would be more likely a P0A78.

 

you can check the pump by looking in the reservoir for movement while the car is ready.

 

There are a few here that use Tech Info regularly, @ChapmanF, being one of them. Hopefully, someone will chime in with some guidance.

At the risk of "teaching grandma to suck eggs", you did create an account first, right?

 

Do you have any browser extensions such as NoScript in use?

I am a NoScript user, and I know I have to tell it to allow a few domains before the techinfo stuff works.

Or maybe it's simpler at the moment: I clicked the Subscribe button just now and got a "site is down for maintenance" page.

-Chap

 

I'd be surprised if it needed old versions of windows to work properly. But not entirely surprised.

Back to your code, there should be freeze frame data for this code, P0A72, which is signified by the snowflake icon (yes, that is what that is) to the left of the code on the screen. (If you saved the data, you can go in offline and look at it, you don't need to be connected to the car.) You are looking for 5 lines that are labelled Detail Data 1 to 5 (or something very similar). These detail data codes are call sub-codes and are helpful to direct where to look in more detail when troubleshooting. Can you see if there are sub-codes and what they are please? In addition, can you tell us what ECU posted the code – this is the detail on the very left of the page in red.

Thanks.

 

It is possible, albeit a final conclusion.

The workup for this code/sub-code combination indicates the trouble areas to be

• Wire harness or connector
• with converter inverter assembly

The diagnostic troubleshooting procedure would have you test the wiring harness and connector for problems and repair/replace. If the harness and connector test ok, then the conclusion is the fault is in the inverter assembly and the inverter assembly should be replaced.

This link: P0A72 | Diagnostics – Hybrid Control System | TIS is an excerpt from the Hybrid Control System repair manual, which should be identical to the information on TIS, and has the procedure for checking the wiring harness and connector.

If you do need to replace the inverter assembly, look to the second-hand market as these are quite cheap compared to new, and the low failure rate means the second-hand ones are reliable and in good working order, as always though, caveat emptor.