Fuel Tank Leak Detection Control Module -J909- / Fuel Tank Pressure Sensor -G400-, CHECKING: Function

The system can test the evaporative system integrity by applying a vacuum signal, ported or manifold, to the fuel tank in order to create a small vacuum. The Engine Control Module -J623- then monitors the ability of the system to maintain the vacuum through signals sent from the Fuel Tank Pressure Sensor -G400 - / Fuel Tank Leak Detection Control Module -J909 -. If the vacuum remains for a specified period of time, then there are no evaporative leaks, and a PASS is reported by the Engine Control Module -J623 -. If there is a leak, the system either will not achieve a vacuum, or a vacuum cannot be maintained. Usually a fault can only be detected after a cold start..

Special tools and workshop equipment required 

• Multimeter
• Wiring Diagram
• Scan Tool