Note. For component terminal identification, see TERMINAL IDENTIFICATION in this article. For wiring diagrams, see WIRING DIAGRAMS - 2.0L TURBO article.
- Remove ECT sensor. Immerse ECT sensor probe in hot water and check resistance between ECT sensor terminals, while heating ECT sensor. Resistance should be 5.1-6.5 k/ohms at 32°F (0°C), 2.1-2.7 k/ohms at 68°F (20°C), 0.9-1.3 k/ohms at 104°F (40°C) or 0.26-0.36k/ohms at 176°F (80°C). If resistance is as specified, go to next step. If resistance is not as specified, replace ECT sensor.
- Turn ignition on. Check voltage between ground and ECT sensor connector terminal No. 1 (Black wire). Voltage should be 4.5-4.9 volts. Go to next step.
- Check continuity between ground and ECT sensor connector terminal No. 2 (Black/White wire). If voltage is not as specified or continuity does not exist, go to next step. If voltage is as specified and continuity exists, check ECT sensor connector. If ECT sensor connector is okay, replace PCM.
- Check PCM connector and wiring harness between PCM and ECT sensor connector. If connector and wiring are okay, replace PCM.