Diagnosis & Repair Procedure

NOTE: For better performance and results of this diagnostic procedure, usage of appropriate wiring diagram is recommended. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.

NOTE: Perform all voltage and resistance tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use an ohmmeter to isolate wiring harness shorts or opens.

If engine system check has been performed, go to next step. If engine system check has not been performed, perform TEST D: ENGINE SYSTEM CHECK under SYSTEM TESTS, then go to next step.
Turn ignition switch to LOCK position. Disconnect ECM harness connector G04. See Figure. Also disconnect EVAP-CVV 2-pin harness connector L92. See Figure. Measure voltage between ground and ECM harness connector G04 terminal No. 7 (Blue/White wire). See Figure. If voltage is zero volt, go to next step. If any voltage is found, repair short to voltage in Black/Red wire between EVAP-CPV, main relay and ECM. After repair, repeat DTC CONFIRMATION TEST .
Turn ignition switch to LOCK position. Perform EVAP-CVV component test. See EVAP CANISTER VENT VALVE under FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EVAP-CVV is okay, go to next step. If EVAP-CVV is faulty, replace as necessary and repeat DTC CONFIRMATION TEST .
Ensure ignition switch is in LOCK position and EVAP-CVV harness connector is connected. Disconnect ECM harness connector G04. See Figure. Measure resistance between ECM harness connector G04 terminals No. 8 or 23 (Black/Red wire) and ECM harness connector G04 terminals No. 7 (Blue/White wire). See Figure. If resistance is less than 40 ohms at 68°F (20°C), substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST . If resistance is 40 ohms or more at 68°F (20°C), repair short circuit in Black/Red or Blue/White wire between EVAP-CVV, main relay and ECM. After repair, repeat DTC CONFIRMATION TEST .