I’ve had the Check Hybrid system message three times now. Every time at slow speeds (25-35 mph) and hot outside temperatures. I think the car was in EV mode each time. Otherwise the car seems fine, no loss of gas mileage and the car runs great at highway speeds. Idles fine in the heat with the air conditioning running too. 1st time I was running about 35 mph on a rural road. When I had the codes checked the report also indicated the 12V battery was low, less than 12 volts. I replaced the battery and everything was fine for several weeks including a 200 mile round trip on the highway. 2nd time was about 35 mph on an urban road. Was out of town and needed to get home so I reset the codes via OBD2 and again everything seemed fine after some more urban driving and about 100 miles of highway. Cleaned the battery fan filter and it was dirty. 3rd time was about 25 mph on a suburban street. Again cleared the codes via OBD2 and everything seemed fine. No issues on the highway and left the car idling in the parking lot while I ran into a store. The Hyper Tough Bluetooth OBD2 I got from Walmart doesn’t connect to the Dr. Prius app. Ordered the Panlong Dr. Prius recommended and it should be delivered today. Any ideas for issues I should look for?
Your car has a high-voltage battery with fewer modules than the Prius Gen2 and Gen3. It should cost a third less. You can also find individual modules to replace the ones that have failed. First, diagnose the battery, perhaps only one or two modules are faulty.
