P1118 need to drain coolant to replace ECT sensor on storage tank?

Question

2004 Prius. P1118 error code. Recommended to test replace the ECT sensor on the coolant storage tank. I think I can do it myself, but don't know if coolant must be drained prior to removal of old part, testing and replacement.

Answer 1

On the coolant storage, you just remove the sensor and allow the coolant to flow out, it is adviseable  when you remove the sensor replace, the reason even if the vehicle is turned off , the water pump can still operate, when you are done installing the new sensor you bleed the hybrid cooling by opening its valve and leading a clear hose into its coolant recovery, P1118 mean this sensor is circuit high taking close look for anything that would cause the connection to the sensor to have a poor connection