PHASE 2 - LEAK DETECTION
The ECM energizes the Change Over Valve allowing the pressurized air to enter the fuel sys-
tem through the Charcoal Canister, The ECM monitors the current flow and compares it
with the stored reference measurement over a duration of time.
Once the test is concluded, the ECM stops the pump motor and immediately de-energizes
the change over valve. This allows the stored pressure to vent thorough the charcoal can-
ister trapping hydrocarbon vapor and venting air to atmosphere through the filter.
36
