Trouble Symptom
When the ignition switch is turned ON, with engine off, MIL does not illuminate.
- Check output signal form Engine Control Module (ECM). Turn ignition ON and measure the voltage between ECM connector B137, terminal No. 15 and chassis ground. If the measured value is less than 1.0 volt, go to step 4. If the measured value is more than 1.0 volt, go to next step. (Scheme 78)
- Check for poor contact at ECM. If the MIL illuminates when shaking or pulling on the ECM connector, repair poor connection as necessary. If the MIL does not illuminate while shaking or pulling on the ECM connector, go to next step.
- Check the ECM connector to ensure connector is properly connected. If the ECM connector is properly connected, replace the ECM. See «ENGINE CONTROL MODULE»(/subaru/impreza-wrx/gdgg-2002-2005/remont/removal-installation/#engine-controls-removal-installation-impreza-outback-sport) under COMPUTERIZED ENGINE CONTROLS in REMOVAL & INSTALLATION article. If the ECM connector is not properly connected, repair connector as necessary.
- Check harness between combination meter and ECM connector. Turn ignition OFF. Remove the combination meter and disconnect the connector. Disconnect the ECM connector. Measure the resistance between ECM connector B137, terminal No. 15 and combination meter connector i12, terminal No. 6. If the measured value is less than 1.0 ohm, go to next step. If the measured value is greater than 1.0 ohm, repair open circuit in harness between ECM and combination meter connector or poor contact in coupling connector. (Scheme 78)
- Check for poor contact in combination meter connector. If there is a poor contact in the combination meter connector, repair as necessary. If combination meter connector is okay, go to next step.
- Check harness between combination meter and ignition switch connector. Turn ignition switch ON. Measure the voltage between combination meter connector i10, terminal No. 7 and chassis ground. If the measured valve is more than 10 volts, replace combination meter. If measured value is less than 10 volts, replace blown fuse No. 13, repair open or short in harness between fuse No. 13 and ignition switch battery terminal, or repair poor contact in ignition switch. (Scheme 78)
