Short trip to Lowes found me with a red triangle and dash lights. Wasn't far from my house, so I turned around to go back home and found that the engine was off and the car just kept decelerating until it stopped altogether. Turning it off and on again allowed for the engine to kick on briefly, but then it'd turn off and I'd be stopped again. Got some help and managed to walk the car in neutral all the way back home. Unfortunately, this whole process drained the hybrid battery. Now the engine won't come on at all and the dash systems won't turn off (I have to unplug the 12volt to turn everything off). I assume it's in limp mode, but its a little odd because it'll flash all the drive indicator lights (park, neutral, drive, etc) and gas level meter. OBD scanners (we tried two different brands) come back with a linking error, like it can't communicate with the computer at all. Any idea what's behind this?
One thing is certain, you will need to charge the HV battery before trying to do anything else. The dash part of that might indicate you have a problem with the combination meter (CM). This is not an unusual problem and is usually caused by a failed capacitor on the CM.
Welcome to PriusChat!! Start by checking the 12v battery health, and recharge as needed. As @dolj mentioned above, you'll also need to charge up the HV battery at some point, use a DIY "grid charger", or a retail version of such. When was the last time the inverter coolant pump was replaced?
Step 1 is to ensure the 12v battery is charged adequately for troubleshooting. Your symptoms of : because it'll flash all the drive indicator lights (park, neutral, drive, etc) and gas level meter. are common indicators of the 12v battery being extremely weak/discharged. If the 12v gets disconnected (or lost) while the car is on, (iirc) the power source ecu will remember that, and the car will stay on when the battery (12v) is reconnected. You need to get the 12v situation sorted out, then go through a normal shutdown procedure, then it should be back to normal. Then start looking at why the car failed to run.
Usually, when you find yourself wondering that, you can go to Recent Posts and look for how recently somebody bumped the "This website is going ballistic" thread. When the server is acting up, often people try to post something, and get errors or timeouts, and aren't sure it really posted, and retry (and sometimes retry and retry). Happened to me a few times before I got wise to it, and now after an error or timeout I'll usually check the thread in another tab to see if the post showed up, and only retry if it didn't. But not everybody does that.
Aside from the on-screen indicator while it was happening, it's that the engine wouldn't kick on when I was limping it home. Car ran out of juice. Thank you. I'll get that battery tested and and swapped if needed. Last time it went bad, it was fast and I didn't see this behavior with the lights, but it's good to know that's the sign. Thank you for the info on the grid charger. I didn't know those existed and was fretting some about how to charge the HV battery. Coolant pump was replaced in 2019.
Update: Took the 12volt battery in to get tested and it is a good battery with a good charge. Put it back in the car and the triangle light went away. ICE still will not turn on.
2007 Toyota Prius. Triangle light and engine warning lights on. No able to get in gear. Needed a push to move it back. Only way it ran was in ‘B’. I was going maybe 25 mph. The mechanic said he knows Prius’s still going 200K. No clear diagnosis. Inverter? Transmission? The inverter piece installed could cost 5K. This car served us well these 17 years. Donating it to a charity. Where we live, there’s only street parking which takes a toll. No vehicle in our future, at least for now.
Why not get the codes read to see what's going on with it? Are you fortunate enough, location wise, to not have a need for a vehicle?
An easy installation job, and a very handsome profit when a used inverter only costs them $75 at a junk yard. Find a new mechanic, for the current prius or for the future. Those warning lights mean 'codes' are stored in the ECUs, use a scanner then post the codes here for guidance. If this was a paid for diagnostic from a dealership, the codes could be on the receipt.