Overheating just after Dealer engine coolant and inverter coolant replacement

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Woodstock74, Feb 10, 2024.

  1. Woodstock74

    Woodstock74 Junior Member

    Joined:
    Aug 26, 2022
    18
    4
    0
    Location:
    Charlotte, NC
    Vehicle:
    2008 Prius
    Model:
    N/A
    2008 Gen 2, w/152,000 miles, just coming back from dealer after having an oil change, engine coolant and inverter coolant changed, red triangle of death flashed briefly (maybe 10 seconds) along with an overtemp warning on the mult-function display. This was maybe 10 minutes after leaving the dealer. I opened my Torque app as I was trying to find some place to pull over (was almost in my neighborhood) and I see 240 F and shut her off immediately after pulling over. Open hood to cool down and try and reach my service tech I had just left, to no avail (end of day for him, so knew it was a long shot). Let the car cool for about 20 minutes and then drove home, about 2 miles away; entire time temp was in the normal range, 180-190ish. Let her cool again for 40 minutes and took her around the block but again the temps started to exceed anything I normally see, peaking around 240 as I pulled into the driveway. The radiator fan also was coming on; ambient was 65F. I checked Torque and there are no codes being thrown that it can see, and I haven't seen the red triangle of death again except that initial time. So naturally the dealer is now closed for the day and there's nothing I can do until Monday. What could I be looking at? Poorly bled system? I did notice coolant spilled around the engine area, flecks here and there on some of the topside covers, nothing really outrageous, just sloppy, and also on the top side of the undertray after reaching up and noticing the undertray was poorly secured; but it's not an active leak as far as I can see and the level looks OK. Thoughts?
     
  2. Aloe

    Aloe Junior Member

    Joined:
    Jan 21, 2024
    59
    5
    0
    Location:
    Canada South
    Vehicle:
    2006 Prius
    Model:
    N/A
    As a noob that just changed own my own inverter pump, I'm wondering if the mechanic plugged the electrical connector back on? You can check that or see if the pump is working. It will vibrate (will feel obvious) when on and you can feel it when you touch the hose close to it or the pump itself.
     
  3. Brian1954

    Brian1954 Senior Member

    Joined:
    Jan 31, 2021
    1,501
    579
    0
    Location:
    South Central PA, USA
    Vehicle:
    2011 Prius
    Model:
    III
    I assume that the engine is overheating, correct, and not the inverter, you really did not say.

    The first thing to do is check and make sure the drive belt is installed on the engine water pump. Next, check the coolant level in the radiator to make sure it is full.

    Was the engine coolant thermostat replaced during the service?
     
    Aloe likes this.
  4. Mendel Leisk

    Mendel Leisk Senior Member

    Joined:
    Oct 17, 2010
    57,960
    39,991
    80
    Location:
    Greater Vancouver, British Columbia, Canada
    Vehicle:
    2010 Prius
    Model:
    Touring
    Leave it parked for the weekend and contact dealership.
     
    nolotank likes this.
  5. jdenenberg

    jdenenberg EE Professor

    Joined:
    Nov 21, 2005
    3,898
    1,900
    1
    Location:
    Trumbull, CT
    Vehicle:
    2020 Prius
    Model:
    LE AWD-e
    A common problem after a coolant change is air in the system. Check the coolant level and as Mendel said, have the dealer purge the system and add more coolant. When this happened to my 2004 Prius a while back, The dealer had to flatbed tow my Prius back to his shop (I offered to do it myself if they gave me a gallon of SSL coolant) as I was not going to stress my engine by overheating it.

    JeffD
     
    Brian1954 likes this.
  6. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    11,170
    1,950
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    You probably don't need to take it back to the dealer unless you just want to do that because of the principle of things I wouldn't have taken it there in the first place to have coolant changed and bled and they should have nothing to do with your inverter that should be your engine overheating I don't think you get it overheat light for the inverter overheating you get the red car in the MFD display indicating something's wrong and then eventually the human that owns the car will figure out that the AM2 fuses blown or the pump itself is blown and the plug on the pump or the receptacle on the pump may even be damaged unplugging that and replacing the AM2 fuse will usually put the red car on the MFD back to green but you will have no inverter pump If it's under 70° outside you may never notice any throttling back of charging or any of that above 70 and humid you will If you drive anywhere worth discussing say over 5 mi maybe 10 so if you're under 5 or 10 mi you may never see any throttling back from the inverter but what you have here is engine overheating. Let it sit overnight in the morning before you touch the start button or anything undo the hood lift the hood look at the jug the one that's right behind the radiator where the coolant goes not the radiator cap what's that jug look like Is it full almost to the plus sign in the bottom of the field neck of the outboard tank the opaque jug? If not fill it up to that plus sign that you're looking down at when you're pouring the cooling in put it right at the bottom of that or level with that now start the car. Unfortunately with the Prius because it's so cold natured and all of that unless you're in Texas and it's 100° out You need to take the car for a drive preferably down the state highway black and white sign where you can go like 50 miles an hour Do that for 10 or 12 minutes 15 maybe and then pull over in a parking lot and whip open the hood again If you haven't seen the overheating light just leave the car running it'll stop all by itself in a second and then look at your coolant in the opaque jug again has it dropped bring it up to the plus sign again do a drive again. Check the cooling again now it hasn't dropped anymore. You should be done or you can go back to the dealer and they can use a machine to push the coolant through and make the loop and go back into their machine until there is forcefully nothing in there except red Asian coolant but that's unnecessary but it may be good for your mental health.