Possible Causes
WARNING: This page is about a different car, the 2003 Toyota Land Cruiser. However, it is still accessible from the selected car via links, so may be relevant.
For DTC detection conditions and possible causes, see Fig 1.
After confirming DTC P0115, use Toyota hand-held tester or scan tool to access CURRENT DATA to read the engine coolant temperature for ECT sensor. If displayed engine coolant temperature is -40°F (-40°C), ECT sensor circuit may be open. If displayed engine coolant temperature is 284°F (140°C) or more, ECT sensor circuit may be shorted.