2009 Prius not starting, MFD screen black

I have a few questions and need help troubleshooting for my boyfriends 2009 Prius since he is at work right now. We want to check to see if there is anything we can do before sending it off to a shop.

I assume it was fine on his way to work but when he got out to start the car it refused to work. He claims it might have been the engine immobilizer being triggered because he accidentally tried to start the car with the fob halfway into the starter slot.

When I went over there to look at the car I noticed a few things weird with it. The multi display is not coming on at all. The car will unlock but the other doors were being extremely stubborn about unlocking. The back hatch refuses to open despite beeping that it is aware of the fob being near it. The power windows roll down and up very slowly. I assume it's battery related ( the 12v ) but I wanted to be sure before we did anything else with it because it also has the red triangle of doom. I took a picture of the dash display in case it helps.

technical by Morphyn posted Jul 25, 2017 at 8:24 PM

Also, in case it is related. When he last got the car serviced they replaced the engine coolant sensor.

So my questions are did he trigger the engine immobilizer and if so how do we fix it? Is it a bad 12v battery or some other electrical problem?

 

An update on the 2009:

So he managed to get a jump last night and his car is back in working order. He also stated the fuel efficiency improved significantly. Should he still get the 12v battery tested to make sure it wasn't the initial cause?

 

Oh boy... so we thought it was fixed...

The check engine light came on and the computer threw out a pretty good list of problem codes:

C0200 - Right Front Wheel Speed Sensor Signal Malfunction
C1241 - Low Battery Positive Voltage or Abnormally High Battery Positive Voltage
C1242 - Open Circuit in IG2 Circuit
C1256 - Accumulator Low Pressure Malfunction
U0126 - Lost Comm. w/ Steeping Angle Sensor Module
***P2601 - Coolant Pump Control Cir. Range / Performance

He thinks the AAA guy jumped his car wrong by incorrectly placing the negative cable. However there are a few other factors. It had a similar issue when he bought the car but it worked fine for awhile. We also just had a pretty significant thunderstorm roll through here with a pretty good downpour.

I checked out the car myself just now and the computer inside the car had a warning about the "P" lock mechanism malfunctioning. It will start if you follow the instructions to apply the parking brake.

I think this is actually probably residual problems from the accident the car had prior to purchase but I wanted to be sure that this was not the result of the AAA guy jumping the car incorrectly.

 

I checked it out again this morning and the 12v is definitely bad. Is there a place I could take it for him that can change it out real fast? Assuming it will actually start that is.

 

Good news! We fixed it. Had to go to the dealership to get a replacement battery though. It was roughly $250 for just the battery. We installed it ourselves because the car wasn't going anywhere. That battery was super dead.

Everything is in working order now. Thank you for all the help and advice everyone!