ECT Sensor 1 Replacement

Drain the engine coolant (see COOLANT CHECK ).
Disconnect the ECT sensor 1 2P connector (A).

Fig 1: ECT Sensor 12P Connector, ECT Sensor And O-Ring With Torque Specifications
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove ECT sensor 1 (B).
Install the parts in the reverse order of removal with a new O-ring (C), then refill the radiator with engine coolant (see COOLANT CHECK ).