Diagnosis & Repair Procedure
NOTE:
Fuel tank pressure sensor and fuel temperature sensor are built as a single unit (assembly), and is located on fuel tank.
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 A-4: ENGINE SYSTEM CHECK under SYSTEM TESTS, then go to next step.
- Turn ignition switch to LOCK position.Check EVAP-CPV circuit. See EVAP CANISTER PURGE VALVE CIRCUIT under FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EVAP-CPV circuit is okay, go to next step. If EVAP-CPV circuit is faulty, go to step 4 .
- Perform FTP sensor component test. See FUEL TANK PRESSURE & TEMPERATURE SENSOR under FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If FTP sensor is faulty, replace FTP sensor and repeat DTC CONFIRMATION TEST . If FTP sensor is okay, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. After repair, repeat DTC CONFIRMATION TEST .
- Perform EVAP-CPV component test. See EVAP CANISTER PURGE VALVE under FUEL EVAPORATION under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article. If EVAP-CPV is faulty, replace EVAP-CPV. After repair, repeat DTC CONFIRMATION TEST . If EVAP-CPV is okay, check for open or short circuit in Blue/Black wire between EVAP-CPV and main relay. Also in Green/Black wire between EVAP-CPV and ECM. If short or open circuit is found, repair as necessary and repeat DTC CONFIRMATION TEST . If short or open circuit is not found, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .