Conditions for Running the DTC

WARNING: This page is about a different car, the 2011 GMC Yukon, 2011 Chevrolet Tahoe, and 2011 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.

P0451

DTC P0451 runs only when the engine-off natural vacuum small leak test, P0442, executes.
The number of times this test runs can range from 0-2 per engine-off period. The length of the test can be up to 10 minutes.

P0452 and P0453

DTC P0452 and P0453 run continuously when the ignition is ON.

P0454

DTC P0454 runs only when the engine-off natural vacuum small leak test, P0442, executes.
This test can run once per engine-off period. The length of the test can be up to 10 minutes.
A refueling event is not detected.