The inf display displays check hybrid systen the code dc dc converter performanc

Thanx alot for your comment but our dealers need these guessworks I don't know why they said the inverter is not the original one ok even so the car still working the error from my engineering view some lose either by the biasing 12 v or the connection because the error happens sometimes not always the dealers sometimes don't want to work or to use analysis to fix the exact problem thanx again appreciated

So , what are you saying? The Toyota dealer won't fix it , can't fix it , or the symptom you describe is not occurring for them in order for them to diagnose? OR that they don't have a tech with the balls to work for free until it's figured out..............? Tell me the specific code(s) Maybe I can get further info........I don't know how Toyota tracks their hybrid parts , but on Hondas' , they have serial #s on the batteries , motor control modules and DC-DC inverters in order to track them. Are you the original owner?

Thanx alot the car was used I bought it month ago and the problem. Is when I drove the car long distance with speed more than 80 kmh the problem occurred check hybrid system then I restart the car it worked I went to the tech.they checked the code it was dc dc converter I don't know if its p0a94-127 or something else they checked the dc dc converter it was ok the smart unit ok the battery charges and discharges ok but the thing iam not really sure the 12 volt battery is not the original its replaced by the previous owner with 45 amp where the original is 65 amp does the 12 volt battery effect the performance of the dc dc converter...and I went to Toyota dealer the thing they do checked the code with analyze the problem they r interested for selling the equipments other than fixing other used cars not under their warranty iam sorry but if you have the good way to start fixing and analyze the problem by which device we must check one by one in order to avoid many guesswork and appreciated your advice once again

Once again , I'll reference Honda , since that's what I'm more familiar with. IF the 12 volt battery is failed OR incorrect , that may cause codes to be set , that otherwise wouldn't occur. I'm sorry , but without punctuation , I'm not sure I am correctly interpreting what you are saying. From what I'm understanding so far , the first thing I'd suggest , is to have Toyota replace the 12 volt battery---I'm assuming it even has one , since looking it up online , Autozone doesn't even list one. IF aftermarket doesn't have one listed , then it's a good possibility that what's in there now may be causing a problem. IF one battery from a dealer actually fixes it , it may save you a LOT more ,by avoiding other guesses , frustration and money. Good luck.

Thanx will replace the battery and check next step will change the inverter water pump and let you know

Let me know if just the battery makes a difference (You will do Toyota , right?).