P0A94 code, without sub codes

Hi all, first post so please be gentle

Gen 3 Prius owned just short of 2 years, trouble free apart from some errors 6mo ago caused by a failing 12v battery, replaced 12v and all was good.

Yesterday I hard accelerated from stopped into fast moving traffic (PWR button on), I felt a jolt / hesitation, and car slowed dangerously, (surprised i wasn't rear ended). Car was still running all be it in a low power state, must be some sort of limp home mode, petrol engine running constantly and appears to be no drive power from electric side of things, however the HV battery is still charging (inefficiently) and I still have 14.8v on the accessory circuit

I have warning lights on the dash and "check hybrid system" on the display. the car will switch on and off and go into ready mode, but stays in this limp mode state with all the warnings. Is it safe to drive in this limp mode or could I do more damage?

Toyota service tech had it today for 1 hour for diagnosis, and pulled code P0A94 but he said he can't retrieve the sub codes, so he can't pin point the problem, he was going to call Toyota Technical. he told me it was probably something to do with the invertor or transaxle but at the moment can't pin point what it is. They have kept the car for further investigation.

Is this a common problem retrieving the sub codes?

I have been reading about inverter failure and the fact that the US have a 15yr warranty if it goes, but not sure how that works here in the UK. It has had all its recall's done, apart from the very recent (stalling) one.

I'm feeling this may get expensive!!

 

Hi 118k miles

 

Hi M.Wynn,
Thanks so much for this, its good to have some ammunition if it is the inverter.

 

If my problem is indeed the inverter and i got hold of a salvage unit, i'm confident and competent about swapping it out, being aware of isolating and taking all the HV precautions.

My question is will it need any kind of programming/mapping to the car?
or can i just drop another one in (if it's not a broken one of course)

will the fault codes and "limp mode" clear ??

If it does require programming/mapping this is where I would be stuck, since I don't have the scan tools

 

Good News

I found a used inverter on eBay £175 ($225), arrived yesterday, so collected the car from Toyota dealer and had a go at swapping it out today.

Success!! it works again.

there's a great how-to video on youtube here

I may still take it in to Toyota dealer to see if they can apply the software that US and Canada got back in 2014 (we never had it in the UK,or the extended inverter warranty). am now concerned this one will go without the fix. Driving like a nun lol. Was hoping to get 200k miles out of this car!

For information the unit i took out was G9200-47140 (2009), and the replacement was G9200-47181 (2011).

Thanks all for your help and advice