Overview of Troubleshooting
- To determine the cause of DTC P0456, a performance test is needed. The performance test uses a mechanical vacuum gauge and scan tool set on the fuel tank differential pressure sensor (TANK PRES SNER 73). The mechanical gauge reading is used to verify scan tool reading. A comparison of the mechanical gauge to scan tool determines the problem in the system.
- Prior to doing the performance test, several simple inspections are needed to exclude some possibilities of the symptom.