My son recently purchased a 2006 Prius and the check engine was on I scanned it for codes and a P0117 had stored (current & pending) I want to circuit check the system but I'm not sure which sensor sets this DTC, first one I encountered was on the drivers lower front side, then I saw some information on replacing one on the back side of the engine (closer to the bulkhead/firewall) I think its the back one since it's part of the ICE system (internal combustion engine) but I want to make sure before I dive into it. Any information on this would be a great help, Thanks
You'll need to double check the sensor, connectors, and wiring with an ohm meter. Those temperature sensors are just heat sensitive variable resistors that rarely fail. On the Prius, it's most likely the 3-way coolant valve is stuck; drivers side next to the inverter coolant pump; if so equipped. It's a plastic valve that gets jammed up when you don't change your coolant or you get contaminates in the coolant (ie. stop-leak). Also check the water pump and belt. Good Luck....
