prius poa93 ??

Discussion in 'Toyota' started by phoebeisis, Jun 25, 2011.

  1. phoebeisis

    phoebeisis Well-Known Member

    The 2006 Prius just showed a triangle on the dash.
    The scan gauge showed code POA93??
    Looked up online says something about impending failure of inverter fan??

    What is up?
    Wasn't there some sort of recall on some part?

  2. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Super Moderator Staff Member

    Recall was for a potential leak of the inverter pump.

    It's an error relating to the inverter cooling system.

    That is not something you want to fail.
  3. phoebeisis

    phoebeisis Well-Known Member

    Thanks for the info.
    I did a quick search and found something that gives me hope that Toyota will be on the hook for this repair- not me.

    The inverter list for just $2000-ha,ha-
    it sure is about the money when it is $2000+!!

    PS I found the below- apparently the inverter cooling pumps regularly fail-hence the recall

    Toyota Prius Inverter Water Pump Recall

    imageInverter water pumps are a common failure on second generation Toyota Prius (model years 2004-2009). Read LG’s original blog here:

    Prius Code P0A93: Inverter Water Pump Failure dated 3/2009

    Toyota issued a “Technical Service Bulletin” on this issue over two years prior, dated January 26th, 2007. Download a copy:

    TSB EG001-07: M.I.L. “ON” DTC P0A93, INFORMATION CODE 346 via PriusChat

    In short, inverter pump replacement is old news. What’s new is that the dealer will perform the service for free, at least until November 30th, 2013, as announced yesterday (read a regurgitated press release from regardless of whether the pump is working or not.

    Read the Toyota Letter to Owners here

    Officially a “Limited Service Campaign”, no doubt everyone will call it a recall and the press will spin about Toyota quality and hybrid doubts, etc.. IMO it’s a “recall” with less urgency and “limited” duration. Given sufficient free time, I will compose a blog about manufacturer response to common failures in the internet age, titled “Service Campaigns: Don’t Call It A Recall”.

    According to Toyota, the concern is air getting trapped in the impeller “causing pump actuation to be slow.” It is possible for air to get
    Last edited: Jun 25, 2011
  4. Harold

    Harold Well-Known Member

    Did you not get a notice from Toyota to come in and have them change the inverter pump? Check with ignition on and see if you can see the fluid circulating in the tank. If not, get it in ASP. A new inverter is closer to 5 grand! H
  5. phoebeisis

    phoebeisis Well-Known Member

    Where in the engine bay is this cooling tank?
    I took a quick look-saw three tanks-windshield washer, brake fluid and

    Is that the tank for the inverter coolant -red fluid middle of engine bay?

    My wife now says "we might have gotten another notice, but I thought it was just the same "rug" notice."

  6. Harold

    Harold Well-Known Member

    It is the tank in the middle. It contains the coolant for the trans-axle. Hal
  7. Harold

    Harold Well-Known Member

    Sorry It is the inverter tank not trans-axle tank although I believe they are related. I haven't had my Prius that long, so still learning. H
  8. phoebeisis

    phoebeisis Well-Known Member

    Does it constantly circulate whenever the ignition is on-even when engine is off?
    PS Just checked- no fluid movement at all-even with the engine idling.
    I looked thru the translucent plastic-then took the cap off- no movement.
    Will there always be fluid circulating-even when everything under the hood is cold( or as cold as it gets in S Louisiana in June)?
    Last edited: Jun 26, 2011
  9. brick

    brick Answers to "that guy."

    Using a flashlight as a back light, you should see movement (ripples) any time the car is "Ready." If you don't, your pump sounds well and truly dead. Driving the car like that, especially in summer heat, runs the risk of killing the inverter, so don't delay in getting the work done. I would go as far as to recommend that you don't drive the car until it's done, save perhaps a very short trip to the dealer if that.
  10. phoebeisis

    phoebeisis Well-Known Member

    Thanks for the info.
    A question- How do I know the car is "ready?"
    Does it have to "run" a bit or just be "on"(pushed button)?
    I agree with you-We aren't going to drive it-except for the 7 miles to the dealer-and we'll do that as early in the day as possible when the temp is under 78 degrees(NOLA is hot in the summer).
    Amazing how a cheap part($100 apparently??) can sink a car in so few miles.Via eyeball the Prius looks tough to work on- my ancient 216,000 mile gas guzzling 98 Suburban(bought used 195,000 miles $2900) is relatively easy to work on. We don't drive it many miles(3000/yr), so the mpg penalty isn't too bad for a 2nd car.It has been surprisingly reliable(survivor bias maybe)

    Maybe AAA will tow it-not sure if they will but I'll check on that.?
    PS It has been a great, absolutely trouble free vehicle for 5 years-until this of course.
  11. Harold

    Harold Well-Known Member

    Just put the e-brake on and make the car ready.ICE does not have to be running! Check for circulation in the tank. Good luck, Hal
  12. phoebeisis

    phoebeisis Well-Known Member

    There is a TINY TINY amount of movement(the engine actually came on for a time)
    but I checked the windshield washer reservoir and there was at least as much movement on the surface of the washer as the surface of the coolant.

    I'm pretty sure it shouldn't be too subtle-there just isn't any fluid being pumped in and out of that tank.
    PS Now I get to see how accommodating the dealer is.
    Last edited: Jun 26, 2011
  13. brick

    brick Answers to "that guy."

    I went out to play with mine. Seems to me that the car doesn't even need to be in "ready" mode, as my pump runs in IG-ON as well. I can hear it whirring near the driver's side headlight, and when I opened the coolant cap (the system was cold!) I could see fluid flow by. It doesn't seem to move quickly, at least not in my case.

    Here is an interesting, recent PriusChat thread on inverter coolant. I don't find the OP's explanation at all satisfying, but I'm curious enough to bleed my system and see if it does anything. IIRC, the TSB made it sound like air infiltration through a bad seal has something to do with failures.
  14. phoebeisis

    phoebeisis Well-Known Member

    I don't see ANY MOVEMENT in mine.
    I'll check again with a flashlight at dusk- it might be easier to detect with less ambient light.
    but I suspect my pump is dead.

    The MPG suggestion the priuschat guy mentions???
    Hmm, our trip meter is reading 36 mpg for some reason- it usually reads 42 mpg or so.
    I rarely drive it-wife and son drive it-I'm stuck with the lumbering Suburban.Just as well since my wife gets HORRIBLE-single digit- mpg with the Suburban in city driving.

    I wouldn't think a coolant problem could drop the MPG by 10%, but it will raise the resistance , so maybe it does??

    I did notice a spike in mpg in late winter when ambient temp was about 50 degrees-I assumed I had accidentally gotten some pure gasoline- not the 15% ethanol we are stuck with.
    Thanks to all- I'll let you know how the dealer treats us.
  15. Harold

    Harold Well-Known Member

    If you don't see any movement then your pump is dead for sure. You should not have any trouble seeing movement! H
  16. brick

    brick Answers to "that guy."

    Yeah, it's dead. I went out to look again and there was no question that the fluid was moving. It's especially obvious when you take the cap off of the reservoir. If you don't see anything moving when you view it directly, it ain't flowing.
  17. phoebeisis

    phoebeisis Well-Known Member

    Brick-I rechecked it with a flashlight around dawn(so it would be easier to see).
    ZERO movement.

    How in the world does an electric pump die in such a way that it doesn't move at all?
    Does the electric motor "die"
    Or does the blade motor shaft connection somehow get severed?It must be a direct connection-probably plastic-so I can see it just shearing.

    PS We'll be bring it to the dealer when they say they can work on it- maybe I'll precool the fluid in the reservoirwith some ice before the 7 mile trip to the dealer.
  18. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Charlie, I'm afraid chilling the reservoir is going to have limited effect at the inverter because the (likely) narrow tubes will limit convective mixing.

    Your best bet is driving short trips in "cool" weather.

    Is there an XGauge for inverter temperature?
  19. phoebeisis

    phoebeisis Well-Known Member

    Right lane

    We are getting ready to drive the 3.5 miles to the dealer- it is 79 degrees here-8am-NOLA-.
    I actually put a cold pack on top of the inverter case(I'm guessing it is the big silver cube(maybe 1x1x1 feet) and put some wet newspaper and poured a little water on the silver cube.
    I going to take the wet newspaper and cold pack off before leaving-3 minutes from now.
    We only drove it .8 miles home after the red triangle showed up.

    I couldn't actually get anything on top of the reservoir-and since like you say it isn't circulating, so all I would get would be pitiful convection cooling currents. Fingers crossed-hope the 3 miles isn't too harsh a trip.

    Just curious- is the Prius motor an AC motor?? They are more efficient that DC I guess?
    I don't guess it will matter much how I drive it since it is constantly using/changing electric power,right? I certainly won't try to get it to go all electric-since I'm guessing it has to convert DC battery power to AC power??

    Thanks-I'll keep you guys posted on what the dealer does/says
    Thanks again for all the help
    Last edited: Jun 27, 2011
  20. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    The Prius uses permanent magnet AC synchronous motors and you are correct -- the motors are used regardless of driving mode. The motors themselves don't generate much heat but the inverter certainly does.

    Keep the speeds low and more importantly, the acceleration rates low -- that will limit the current peaks and should help with the temperature. I would blip the pedal to get it to use the engine and then drive as gently as you can with the engine running. 3mi is short enough that you'll be stuck in the warm up routine, though. IIRC that runs the engine in a warming cycle while driving the wheels purely in electric -- again, use slow accelerations!

Share This Page