ECT Sensor No. 1

WARNING: This page is about a different car, the 2020 Mazda MX-5 Miata. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the negative battery cable. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION .)
Drain the engine coolant. (See ENGINE COOLANT REPLACEMENT .)
Disconnect the ECT sensor No. 1 connector.
Remove the ECT sensor No. 1 using the SST.

Fig 1: Engine Coolant Temperature Sensor No. 1 With Torque Specification
Courtesy of MAZDA MOTORS CORP.
Install in the reverse order of removal.
Refill the engine coolant. (See ENGINE COOLANT REPLACEMENT .)