1. Attachments are working again! Check out this thread for more details and to report any other bugs.

P0A93 Inverter system preformance

Discussion in 'Gen 2 Prius Technical Discussion' started by CharlesS, Jun 30, 2016.

  1. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
    Was driving my 2007 down the road last night and all the sudden just about every light on the dash comes on, no loss of power, AC didn't turn off, headlights didn't dim. I pulled into a nearby parking lot and popped the hood. Initial check was good, didn't see any smoke, leaking water, or any other major issues. Checked the oil, and found that I was low so since I was parked next to an auto parts store I bought oil and filled it up to the proper level. Turned the car on and the Red triangle & the CEL were still on but the others had gone off. I asked the guy in the parts store to scan the code and it came back as P0A93 Inverter system coolant performance. Neither of us knew what that meant, but figured it couldn't have been good. I drove home with the Red triangle and CEL lights on but no signs of any mechanical problems (no signs of overheating and charging system seemed to be working properly). This morning I checked the fluid level in the reservoir and found it was at the proper level and turned the power on the car and checked the pump, steady hum with no sputtering or sounds of air. Any suggestions from this point?
     
  2. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    was there a swirling motion in the fluid when you removed the cover?

    how much oil did you have to add?
     
  3. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
    Not able to see any swirling motion due to the size of the tank, I can see the fluid in the tank but the opening is so small I can't see very well down through the top. I had to add 2 quarts of oil, which I thought was quite odd since we had just had the oil changed a couple of months ago and don't know why it would be so low (no smoking or leaks).
     
  4. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,464
    8,377
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    Have you done the recall on the pump at the dealer? I've seen they fail close to the 100k miles mark.
     
  5. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i think you need to find a way to see if there's fluid in motion. i have not seen it reported before that you can't see the fluid when you remove the reservoir cap.

    how many miles on her?
     
  6. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
     
  7. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
    Maybe I am not seeing the correct fill mark on tank, how much fluid should be in the tank when full?
     
  8. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
    200K + miles
     
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    it's not how much, you need to know if it's moving. that's how you tell if the pump is working or not.
     
  10. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
    Ok went and checked again, with the car running I checked the fluid level with a flashlight and was able to see fluid moving in the tank.
     
  11. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    okay, more diagnostics needed then.
     
  12. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    might have to have toyota scan for codes that auto zone couldn't find.
     
  13. CharlesS

    CharlesS New Member

    Joined:
    Aug 20, 2015
    24
    2
    0
    Location:
    Buckeye, Az
    Vehicle:
    2007 Prius
    Model:
    Two
    Cleared the codes, drove for about 60 miles and no CEL or red triangle. Only thing that has changed is I added the oil. Could the low oil could have caused the pump to stop working or work less? I could see the low oil causing the lights to come on, but I don't really understand the code if the pump is working.
     
  14. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    could be that the autozone scanner read the code wrong. all scanners are not created equal.
     
    #14 bisco, Jun 30, 2016
    Last edited: Jun 30, 2016
  15. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    btw, it's time to start checking the oil more frequently, at least until you've proven that it's not losing oil, which would mean someone didn't refill properly.
     
  16. M in KC

    M in KC Active Member

    Joined:
    Jun 21, 2014
    358
    106
    0
    Location:
    KC, MO
    Vehicle:
    2005 Prius
    Low oil will not contribute to the inverter coolant pump from working or not. Those two items are completely unrelated assuming you retrieved the correct code to begin with. As brisco encourages, you will need to keep an eye on your oil level more frequently until you have more confidence that the motor is not consuming oil. If you added 2 qts that means there was roughly 1.7 qts in the crankcase and that's no bueno.
     
    bisco likes this.