Warning lights: check engine, VSC, brake warning light

1. check the oil level in your car and make sure you have oil in the engine
2. check the voltage in your 12v battery to make sure it's at least 12.5 - 12.9 volts. If not, charge it back up
3. I would reset the car (by disconnecting the 12v negative for a few seconds). All your warning lights should go away and see if they come back.

If this ends up to be a hv battery issue, I would recommend buying a new battery from Toyota. You can ask Toyota corporate for financial help....but that will take time and you sound like you don't have much time to spare.

 

If the 12V battery is in obviously bad condition then that would be the first item to replace. Otherwise, visit your dealer service dept tomorrow and see what the tech comes up with.

Since a timely repair is your highest priority, do not disconnect the 12V battery if it is in acceptable condition, as that will cause the loss of whatever DTC had been logged. It is OK to disconnect the battery if you have time to play around with the car and wait for the faults to reappear.

The issue is likely a serious one since the red icon in the upper left corner of the MFD is on. That shows the hybrid drivetrain is impaired. And the car may have more than one issue since the check engine light is on, as well as the VSC/brake system warning lights.

 

I just experienced the exact situation, same symbols/lights with my 2005 Prius, 116,700 miles, about 3 hrs ago. Car has been running fine, no issues. Funny thing is, I had just left the dealership after purchasing oil & filters for maintenance. Drove 10 miles and this happened. Pulled over, check engine compartment, all fluids okay, no overheating, etc.. Husband advised to continue home. So, he said he would check the 12 volt battery as discussed above and tomorrow morning take in & have codes pulled. Is there anything else we should do?

 

1. Check the inverter coolant reservoir for fluid turbulence when the Prius is READY. If you do not see this, the inverter coolant pump has failed.
2. Get Mini VCI so that you can be self-sufficient with regards to retrieving DTC on Prius and for that matter, any Toyota vehicle. This provides you with similar capability with regards to retrieving DTC and monitoring many vehicle parameters, as is available to the Toyota dealer techs.

 

Well, checked 12v battery, shows 12.48, charger is connected at this time & charging. Checked for fluid turbulence while READY, there is
zero movement. Taking Prius to friend that has to retrieve DTC, then will see what comes up. Thank you so much Patrick for your assistance & knowledge in this matter.

 

UPDATE: Codes showing are: P0A93 and B2799. So, husband & his friend want to replace inverter coolant pump tomorrow if I can get replacement part. Is anything else you would advise to purchase and/or have performed? What do we need to consider with the code B2799?

 

Yes, P0A93 means the inverter coolant pump needs to be replaced. Your husband should also buy a gallon of Toyota Super Long Life Coolant, to replenish the inverter/transaxle coolant. That system will need around 2.5 quarts.

You may find my 2009 post about how to replace that pump to be of interest. This was written prior to Toyota implementing the limited service campaign to replace the pump at no charge. That program expired in Nov. 2013.
http://priuschat.com/threads/how-to-replace-the-inverter-coolant-pump.65173/
LSC A0N - HV (Inverter) Water Pump; Dealer Letter and Technical Instructions | PriusChat

Regarding B2799, see if that code comes back after you've taken care of the inverter pump. This means a communications failure between the immobilizer ECU and hybrid vehicle ECU. If you are lucky, that is a spurious fault caused by the 12V bus voltage dropping down as the DC/DC converter within the inverter stopped functioning.

I suggest that the engine coolant pump should also be inspected to see whether the pump bearing is leaking. If so then it would be good to replace that pump at a convenient time. The engine coolant system will need ~6.5 quarts if the system is fully drained including the coolant heat recovery system canister.

 

Inverter pump is $102 at Toyota of San Bernardino. 2007 Toyota Prius Parts - Toyota of San Bernardino Online Parts Store
Maybe you can get your local Toy dealership to beat/match this price, assuming their's is more expensive.

If the inverter pump was never replaced under the LSC (Limited Service Campaign) or the later Safety Recall, you just might be in luck still. Plug you VIN here Lookup Safety Recalls & Service Campaigns by VIN , to see if this recall is still outstanding for your car.

 

Good point on checking about the recall first. I had mine replaced last October when it died on a trip. The out of state dealer who I've never dealt with or did any service with diagnosed it and replaced it for free under the recall.

 

Thank you for the input exstudent, I pulled my paperwork from previous owner and the inverter coolant pump was replaced at 62,452 miles back in Oct. 2011. I purchased Prius in Dec. 2011 with 63,500 miles. Dealer charged full price per paperwork.

So, I called our local Victorville Toyota dealer and he quoted $141 plus tax. So per your suggestion went to their online parts dept. and purchased it for $105 total. Picked it up last night along with a gallon of Super long life coolant.

 

Update: Husband drove car to friends shop to replace inverter coolant pump, NO symbols/lights showing. So Im thinking putting the trickle charge on the 12V battery took care of those for the time being. We will see how it goes after changing out the inverter coolant pump. He is also replacing the serpentine belt while he is working on Prius.

 

If it was a short trip, the inverter may not have gotten hot enough to retrigger the symbols/lights. It will drive and feel normal until it starts getting too hot from the lack of coolant circulation from the inverter coolant pump not working.

dave

 

New inverter coolant pump & serpentine belt installed. Checked for any signs of leaking from engine coolant pump, none found. Drove over 200 miles today, 88 degrees outside, used A/C, all went well. Still No symbols/lights, . Husband will see if any codes come up on Monday. Again, thank you all for your assistance.