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

2005 Prius, several dashboard warning lights

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Tom E, Dec 31, 2023.

  1. Tom E

    Tom E New Member

    Joined:
    May 28, 2023
    6
    2
    0
    Location:
    Bellevue
    Vehicle:
    2005 Prius
    Model:
    Two
    I have a 2005 Prius with ~180k miles. This morning I drove a couple of miles to my father's house, car ran great. About 20 minutes later I was trying to leave. Started the car, backed out of the driveway, all seemed fine. But maybe 5 seconds after I put the car into Drive and started forward I got several warning lights; please see the attached photos. I drove the car until a good stopping point (~50 yds) and turned off the car then restarted. Same lights immediately came on. Turned around and went back to Dad's house.

    Sorry, I have been trying to upload the photos I took of the dashboard to show the lights but I keep getting an error message. Here is a description of what I am seeing.
    Dash display - Red triangle with exclamation point, plus Check Engine, plus yellow circle symbol with exclamation point
    Multi info display - red car with exclamation point

    All of these warnings say "Take car to Toyota Dealer" with varying degrees of urgency. But nowhere do they tell me anything about what they mean.

    I am a decent mechanic, and would like to at least try to deal with this myself before giving my local Toyota dealer a bunch of money. I have already found that in at least some cases I am more competent than they are, after they tried to tell me I had a bad wheel bearing less than a month after I had replaced it (there was nothing wrong with the bearing).

    Is there any way to do a "reset" on the system to see if I get the same results again? I have had other instances where the car gave me strange displays that went away after turing off and restarting the car. But that didn't work this time.

    I'm happy to give any other info that might be helpful in diagnosing the problem, just tell me what you need and the best way for me to get it.

    Thanks in advance for any help!
     
    #1 Tom E, Dec 31, 2023
    Last edited: Dec 31, 2023
  2. JC91006

    JC91006 Senior Member

    Joined:
    Nov 10, 2013
    16,525
    8,428
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2008 Prius
    Model:
    II
    Well do you have a capable code reader to go with your mechanic skills? That will be better than guessing at it.

    If I had to guess, it would either be a bad inverter pump or a bad hybrid battery. But that's just a guessing game.

    You can check for a bad inverter pump easily by opening the cap to the inverter coolant reservoir, look in there when the car is in READY mode and see if the fluid is pumping. If there is no movement, then you have a bad pump.
     
    Tom E likes this.
  3. Tom E

    Tom E New Member

    Joined:
    May 28, 2023
    6
    2
    0
    Location:
    Bellevue
    Vehicle:
    2005 Prius
    Model:
    Two
    I do not own a good code reader, but can borrow one from the local auto parts store. That had been my plan if no one here was able to give me some ideas. Unfortunately regardless of ability to repair/replace faulty parts, it makes no difference if I don't know where the problem is. The info I have been able to find online regarding the meanings of the error lights has been extremely unhelpful.

    I'll try checking the fluid flow in the reservoir after putting the car into Ready mode.

    The car seemed to be driveable even with the lights on, at least I was able to move it 100 yards or so with no problem. My father's house is ~2 miles away on back roads (no fast driving). Is driving the car home for this distance advisable/possible with the current light display?

    Thanks for your help!
     
  4. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,376
    1,792
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    Is the little green car on the center screen now red where it normally is green? Sounds like maybe your inverter coolant pump has bit the dust that's the jug with the pink fluid in between the engine and transmission next to the silver thing that says hybrid synergy drive or your inverter You uncapped that put the car on just for haha's You should see that fluid in that reservoir moving not a lot and there's a pump behind the left headlight that you should hear or feel just by touching the fender feel the vibration You can reach your hand down below mid headlight on the left side and you'll see this pump right next to your hand It's a flat black thing on a gold bracket with two 5/8 size hoses coming out of it
     
    Tom E likes this.
  5. ChapmanF

    ChapmanF Senior Member

    Joined:
    Mar 30, 2008
    24,906
    16,213
    0
    Location:
    Indiana, USA
    Vehicle:
    2010 Prius
    Model:
    IV
    ^ This.

    The yellow circle with exclamation, you can get the trouble codes triggering that without a scan tool, like this:

    Blink (a/k/a Flash) Codes – How to. | PriusChat

    But you have other warning lights too from ECUs that don't do the blink-code thing, so a scan tool is needed to get those codes anyway.

    You can't tell much from just looking at the lights that are on, because those only mean read the codes, and there are hundreds of possible codes.
     
    Tom E likes this.
  6. Tom E

    Tom E New Member

    Joined:
    May 28, 2023
    6
    2
    0
    Location:
    Bellevue
    Vehicle:
    2005 Prius
    Model:
    Two
    Thanks everyone for your help, I really appreciate it!

    Here's the update. Auto parts store was closed today so I have not been able to get a code reader.

    I did check the inverter pump, and it seems to be working. With ignition off fluid is completely still, when on there is small but noticeable movement.

    Here is where it might get interesting. I looked at the Multi Info display in Energy Monitor mode. The battery level is at only two bars and bars are white; usually when I check it (not very often) it is only DOWN two bars from the top, and bars are green. As I did more research online, I read that when the battery is getting near the end of life that fuel economy will drop. I have noticed that for the last month or so my MPG is down 2-4 MPG, but I had figured that was just due to colder weather and subsequent greater use of the heater (and engine). In the last week, when at a stop light the car engine would suddenly turn on and rev up to what I'd guess was ~2000 rpm, much higher than what I would normally experience when stopped even with the heater running.

    So it would appear that either the battery is no longer wanting to take a charge, or that the charging mechanism is not working correctly to charge the battery. I realize that the second possibility opens up a number of options.

    Any other help or suggestions are welcome! Assuming I am able to borrow/rent a code reader I will do so tomorrow, but it may be that the only way to use one will be to take the car to the auto parts store and use it there. From the description of what is happening with the car, do you think that driving a short distance should be OK, or do I need to get a tow truck?
     
  7. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,141
    50,053
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    very likely the hybrid battery needs to be repaired or replaced. but you want the codes before throwing money at it.
    repair is a learning curve and time consuming, rebuilt batteries are often sketchy, and a new battery is around $2,000. plus labor
     
    Tom E likes this.
  8. Tombukt2

    Tombukt2 Senior Member

    Joined:
    Nov 29, 2020
    10,376
    1,792
    0
    Location:
    Durham NC
    Vehicle:
    2009 Prius
    Model:
    Base
    When you get down to the hybrid battery seriously failing you'll drop immediately to like 37 mi to the gallon and your ice engine will never turn off and stop lights and all that just like a regular car that's about all you'll notice and you'll be stepping on the gas more to go the same speed you remember going not too long ago at half throttle that kind of thing but other than that car runs reasonably fine till you can get a battery in it or whatever it'll still start and run all the time.
     
    Tom E likes this.
  9. Tom E

    Tom E New Member

    Joined:
    May 28, 2023
    6
    2
    0
    Location:
    Bellevue
    Vehicle:
    2005 Prius
    Model:
    Two
    Latest update. I took the Prius to my local auto parts store where I have used their code reader in the past to successfully diagnose a problem with the ABS system. But after trying two different code readers we were unable to get any code readout on the battery system. The only systems that could be read gave no codes to pull.

    This seems pretty weird, so I'm wondering if it was a matter of user error, though the guy I was working with seemed to know what he was doing. Is there a particluar kind of reader that I need to locate? Taking it to a shop for a diagnostic is $200, so I'd like to avoid that if possible.

    So far as driving the car, it did fine. But I left the Multi display in Energy Monitor made and the battery level was all over the place, at times showing fully charged and a couple minutes later almost empty. Kind of disconcerting to drive!

    Thanks again to everyone for your help!
     
    bisco likes this.
  10. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,141
    50,053
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    that's a classic sign of the battry going south. it moves up and down quickly because it is taking very little charge and producing the same.
    unfortunately, you need a prius aware scanner like tech stream to be sure of getting all the codes
     
    Tom E likes this.
  11. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,855
    3,968
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    ... or one of the more capable scanners reviewed in this post: Gen2 OBD2 app review
     
    Brian1954 likes this.
  12. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    110,141
    50,053
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    i think dr. prius specializes in the battery