Resistance inspection

Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
Drain the engine coolant. (See ENGINE COOLANT REPLACEMENT .)
Remove the plug hole plate. (See PLUG HOLE PLATE REMOVAL/INSTALLATION .)
Disconnect the ECT sensor No. 2 connector. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION .)
Remove the ECT sensor No. 2. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION .)
Place the ECT sensor No. 2 in water with a thermometer, and heat the water gradually.

Fig 1: Measuring Resistance Between ECT Sensor No. 2 Terminals
Courtesy of MAZDA MOTORS CORP.
Measure the resistance between ECT sensor No. 2 terminals A and B.
- If not as specified, replace the ECT sensor No. 2. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION .)