my 2008 Prius had issues last summer in the intense heat here in Phoenix. A couple times I didn’t garage it and when the temp was 112 it would start, but then never go into gear and eventually the triangle of death. If I let it sit overnight (cool off), I could start it in the morning and use it. This year however it happened when it was only 100 (I know, ONLY 100, sad but true). I don’t feel like it’s reliable anymore. It has just over 200,000 miles. Any suggestions?
Have the DTC/INF codes read and post them here. Park in the shade with the windows down if possible. Clean the HV battery fan. Think about purchasing a NEW main traction battery if you plan on keeping the vehicle longer.
Have you tried using a windshield cover and rolling down the windows as soon as you start the vehicle to bring the temperature down? Also try the above regarding parking in the shade and cleaning the battery fan.
Contact Steve at Phoenix Hybrid Batteries. Consider yourself fortunate to have an expert in your backyard.