DTC P0115 (TW) - ENGINE COOLANT TEMPERATURE (ECT) SENSOR CIRCUIT MALFUNCTION Subaru Impreza GC/GF

Note. Refer to illustration for connector and terminal identification. (Схема №11)- (Схема №29).

1. Turn ignition to OFF. After Connecting SSM or OBD-II scan tool, turn ignition to ON. Turn SSM or OBD-II scan tool to ON. Start Engine. Set SSM function mode to F05 for water temperature indicated in "°F" or F06 For temperature in "°C". If value is more than 300°F (150°C), go to next step. If value is less than - 40°F (- 40°C), go to step 3). If value is between - 40 - 300°F (- 40 - 150°C), repair poor contact in connectors or harness of ECT sensor connector, ECM connector or coupling connector E21. (Схема №11)
2. Turn ignition to OFF. Remove idle air control solenoid valve by-pass air hose. Disconnect ECT sensor connector. With ignition and SSM in ON position, select function mode F05 or F06. If value is less than - 40°F (- 40°C), replace ECT sensor. If value is more than - 40°F (- 40°C), repair short circuit in harness between ECT sensor connector and ECM connector.
3. Turn ignition to OFF. Remove idle air solenoid valve by-pass air hose. Disconnect connector from ECT sensor. Turn ignition to ON. Measure voltage between ECT sensor connector E4, terminal No. 1 and ground. If voltage is 4 volts or more, go to next step. If voltage is less than 4 volts, repair open circuit in harness or poor contact at ECM and ECT sensor connector. Turn ignition to OFF. Measure resistance in harness between ETC connector E4, terminal No. 2 and ground. If resistance is 5 ohms or less, replace ECT sensor. If resistance is more than 5 ohms, repair open circuit in harness or poor contact in ECM and ECT sensor connector.