DTC Description

The PCM closes the Canister Close Valve (CCV) at the charcoal canister to seal off the evaporative emission system and then opens purge control valve (PCSV) to generate a vacuum in the fuel tank. This vacuum generation phase will determine if there is a large leak like tank cap open or canister shut off valve (CCV) stuck open. The PCM sets DTC P0455 if the pressure in the fuel tank does not drop as low as predetermined threshold during predetermined maximum vacuum generation period.

If the same error code is set in the next driving cycle, the PCM illuminates the MIL.