PRIUS 2004 READY is not getting ready-

Hi
Problem and back ground: for PRIUS 2004 Gen 2 , 157000 km, not getting READY to drive.

1.Warning signals on Power ON, red triangle, yellow color engine, brake, ABS, skidding. Also the PARKING BRAKE RED signal (by the side of seat belt warning signal), does not disappear even if I release the foot brake.
2. Gear can move to N and parking P only, can't move to Drive D or Reverse R. No READY symbol,

3. I left the car in that location in open for a month, during heavy rain. But after coming back , the car had no issue and I was driving for 4 days before this issue started.

what I have tried:
1.Have removed the 12 Volt battery terminals and connected back, just to see if the errors disappear. No change. But did not check the battery voltage or suspect it . disconnected and connected the HV service plug.(orange color lever behind rear passenger seat)
2. Have been switching ON and off the car for 1 full day, First day the local Toyota service (non-prius), came to connect to OBD late evening, he switched on the interior lights and lefts doors open, with in 10-15 minutes the lights started dimming. Before he could pull the information, all shut down and 12V battery down. his measurement at battery without removing any terminal showed 3.6V.
3. Second day took the battery out and charged at local battery service guy for 6 hrs, he say's charged at 3A, the indicator showed green, that means fully charged, his measurement with no load 12V. After connecting to car my self, checked the voltage at display by putting to diagnostic mode, showed 12 volt (only with display on) with headlight on and pressing brake drops to 11.6volt. IS THAT OK?

4. Third day got new battery and replaced, showed the same voltage 12/11.6v, but I can't be 100% sure if that is brand new battery, the box was open, and since car didn't start, the battery sales person has taken back the new battery in the same box. I connected back the old battery, it was holding the same voltage. SHOULD I still SUSPECT BATTERY?

5. I can make the READY indication blink twice, if I press hard the brake pedal and hold the POWER button few seconds, during this time I can hear CLICKING NOISE behind at HV BATTERY SERVICE PLUG grip? does that say something?

6.Fourth day, Toyota service person (non-PRIUS) has come to download the error codes, he managed to clear some codes, but could not clear P3030 (ECU to HV battery communication error, also P3000, he need to consult his other location teams. I am stuck at this stage now. The service person also, checked some of the fuses in the engine side, removed/connected the ECU cable below the glove box. ( I am not sure if that is the ECU position?)

Today the 12 battery is at 10 to 11V.

Any help appreciated.

 

Thanks Patrick, for the clarifications, I will next try with 12V battery tomorrow and give the feedback..
meanwhile, when brake pedal depressed and holding the POWER switch for 10 seconds make the READY singal blink twice, does that give any message or symptoms of the problem too..

 

Hi Thanks for the inputs. I did change to new 12 Volt battery measured open circuit voltage at 12.8, and with load headlights , stays at 12 V.
Removed and put back the Traction battery interlock(HV service plug), locked well.
No change in the status, P3030 and P3000 can't be removed. Haven't measured the voltage sense wire leading to ECU.
Planning to tow to service center and ask them to do the checks/measurements.
will keep you updated.
Rgds

 

the car is up now, they found three pins burned (HV Battery ECU connector- orange color), and they have managed to do direct wiring for now. Is that safe, should I prepare for new ECU, what cause shorts in these connector? I do see low MPG also..