2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1370
The ECM tests the Evaporative Emission (EVAP) System for a large leak or restrictions to the purge path in the EVAP system. When the enabling
criteria has been met the ECM commands the evaporative emission canister vent solenoid valve ON and the evaporative emission canister purge
solenoid valve ON, allowing vacuum into the evaporative emission system. The ECM monitors the fuel tank pressure sensor voltage to verify that
the system is able to reach a predetermined level of vacuum within a set amount of time.
The following table illustrates the relationship between the ON and OFF states, and the OPEN or CLOSED states of the EVAP canister purge and
vent valves.
Conditions for Running the DTC
* Before the engine control module (ECM) can report DTC P0455 or DTC P0497 failed, DTCs P0446 and P0496 must run and pass.
* DTC P0100, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117, P0118, P0119, P0443, P0446, P0449, P0450, P0451, P0452,
P0453, P0458, P0459, P0496, P0498, P0499, P0502, P0503, P0560, P0562, P0563, P0700, P2122, P2123, P2127, P2128, P2138, P2227,
P2228, or P2229 is not set.
* The ignition voltage is between 10-18 V.
* The engine run time is greater than 10 min or the fuel trim is stable.
* The fuel tank pressure is between -18.7 and +9.8 mm Hg (-10.0 and +5.2 in. H2O).
* The Closed Loop fuel control is enabled.
* The engine is idling.
* The barometric pressure (BARO) is greater than 68 kPa.
* The fuel level is between 11-88 %.
* The ambient air temperature (IAT) is between 2-32掳C (36-90掳F).
* The engine coolant temperature (ECT) is within 10掳C (18掳F) of the ambient air temperature at engine start.
* The vehicle speed sensor (VSS) is less than 3 km/h (2 mph).
* The above conditions are met for greater than 30 s
* DTC P0455 or DTC P0497 will attempt to run up to 10 times or until the test completes successfully once per ignition cycle.
Conditions for Setting the DTC
* The ECM detects the EVAP system is not able to achieve or maintain vacuum during the diagnostic test. This condition can be the result of a
large leak or a restriction in the EVAP system.
* The condition exists for greater than 4 s or for a cumulative of 30 s.
Action Taken When the DTC Sets
DTCs P0455 and P0497 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0455 and P0497 are Type B DTCs.
Diagnostic Aids
* Inspect for a loose, missing, damaged, or incorrect fuel fill cap.
* Inspect for a damaged fuel filler neck seal surface.
* A blockage or restriction in the evaporative emission purge solenoid valve, purge pipe, evaporative emission canister, or vapor pipe, can
cause this DTC to set.
* The evaporative emission system can be filled with smoke more quickly and completely by opening the system opposite the end where the
smoke is injected. Close the system once smoke is observed.
* To help locate intermittent leaks using the J 41413-200 - EEST , move all evaporative emission components while observing smoke with the
J 41413-SPT - White Light.
* Individual components can be isolated and tested using adapters in the J 41413-300 - Kit.
* A condition may exist where a leak in the evaporative emission system only exists under a vacuum condition. This type of leak may be
detected by using the scan tool Purge/Seal function to create a vacuum in the evaporative emission system and then observe the fuel tank
pressure parameter for vacuum decay.
