Engine Coolant Temperature Sensor
WARNING: This page is about a different car, the 2004 Mazda 6 and 2003 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Before performing the following inspection, ensure to follow the troubleshooting procedure. See SYSTEM OPERATION CHECK under TROUBLESHOOTING.
- Disconnect Engine Coolant Temperature (ECT) sensor. On 2.3L engines, the ECT sensor is located under the ignition coil. On 3.0L engines, the ECT is located in the water bypass tube. See COMPONENT LOCATIONS .
- Remove battery cover. Disconnect negative battery cable.
- Remove plug hole cover.
- Drain coolant into appropriate container.
- Using SST 49 D015 001, remove ECT sensor.
- Place the ECT sensor in the water and while increasing the water temperature, measure the resistance between ECT sensor terminals "A" and "B". See ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE table. If the monitor item status/specification (reference) is not within specification, even though the ECT sensor resistance is within the specification, perform CIRCUIT OPEN/SHORT INSPECTION under SYSTEM TESTS. If not within specification, replace ECT sensor.
ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE
| Water Temperature - °F (°C) | K/Ohms |
|---|---|
| 68 (20) | 35.48-39.20 |
| 158 (70) | 5.07-5.60 |
| 176 (80) | 3.65-4.02 |