Leak Detection System

Leak Detection System

• The function of the leak detection system is based on the premise that the fuel systems creates a natural vacuum when the fuel in the fuel tank becomes colder.

• Temperature and pressure are measured when checking the leak detection system. The fuel tank leak detection control module (J909) - 2 - with an integrated fuel tank pressure sensor (G400) , located on the EVAP canister - 7 -, supplies these values.






• The system is considered to be closed when the measured vacuum is 2.5 mbar as the fuel tank temperature drops.

• There is a leak in the fuel system if there is not vacuum, which will result as an entry in the control module Diagnostic Trouble Code (DTC) memory.

1 Signal wire to the Engine Control Module (ECM) (J623)
3 Bleed line to the engine
4 Fuel tank
5 Fuel tank vent line
6 Air filter vent line