If there are no coolant leaks, replace the thermostat first, if problem is still there check/replace coolant temperature sensor.
Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
The cost to diagnose the P0128 2007 Toyota Prius code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.
The engine coolant temperature does not reach to specified temperature even though the engine has run long enough.
Coolant temperature below thermostat regulating temperature. Indicates that the thermostat monitor has not achieved the required engine operating temperature within a specified amount of time after starting the engine.
Need more information on how to fix the P0128 2007 Toyota Prius code? Get Access to Factory Service Manuals
Get the P0128 2007 Toyota Prius code diagnosed by a professional: Find a repair shop in your area