Help! New owner of 2001 Prius warning light advice

Hello! Love the Prius Chat website and have poured over these threads looking for anyone with my exact problem. Hoping for any advice, please.

We recently purchased this awesome 2001 Prius with125,000 miles. It’s been well cared for and regularly serviced to my knowledge, and according to info found on the Toyota website. We took the Prius to our family mechanic to have the rear struts replaced. This mechanic admittedly doesn’t know much about hybrids but is an excellent, competent mechanic in general. Before the strut replacement we’d driven the car about 2,000 Miles with absolutely zero issues. When I picked up the car, after the repairs were complete, I turned the key and it struggled to start. Actually, it did not start the first try. It kind of gurgled a bit and started rough the second try. That’s when I noticed the headlight icon illuminated on the panel. It appears the mechanic left the headlights on—I don’t know for how long. Immediately after the sputtering engine/slow start, the red triangle appeared along with the red car icon with the exclamation mark. The only other symptom that I can see is that the car no longer predictably starts on the first key turn. It always starts on the second key turn. These red warning lights have remained illuminated since (about two weeks).

We ordered a new 12V battery and replaced it successfully this afternoon. Unfortunately the new battery did not resolve the starting issue nor remove the warning lights. Has anyone been here before? Any advice for me or suggestions about where to go from here?

Thanks in advance!

 

Thank you for the response. The check engine light is not on. Only the red car exclamation and the red triangle. We did take the car to Auto Zone before the new battery arrived in an effort to have any codes captured. The only code they picked up was P0300 Multiple Cylinder Misfire Detected. Any other thoughts are welcome.

I’m currently looking for a local Prius mechanic that is less expensive than the dealership.

Thanks!

 

Just got our Gen 1 Prius back from a local import mechanic with an impeccable bill of health! The warning lights/delayed starting were both caused by a loose wire (knocked loose while having struts replaced).

Thanks for the responses!

 

This is what the service summary receipt says:

Upon inspection and scan, codes present for HY interlock switch. Technician found safety plug not locked in.