Resistance Inspection: Notes

WARNING: This page is about a different car, the 2005 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Remove the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION .)
Place the ECT sensor in water with a thermometer, and heat the water gradually.
Measure the resistance between ECT sensor terminals A and B using an ohmmeter.
- If the ECT sensor is okay, but the PID value is out of specification, perform the "Circuit Open/Short Inspection".
- If not as specified, replace the ECT sensor. (See ENGINE COOLANT TEMPERATURE (ECT) SENSOR REMOVAL/INSTALLATION .)
  
  Fig 1: Identifying Engine Coolant Temperature Sensor
  Courtesy of MAZDA MOTORS CORP.