Code Enable Criteria

WARNING: This page is about a different car, the 2002 Isuzu Trooper. However, it is still accessible from the selected car via links, so may be relevant.

Following conditions must be met for DTC diagnostic test to run:

No Throttle Position (TP) sensor, Intake Air Temperature (IAT) sensor or Manifold Absolute Pressure (MAP) sensor DTCs are stored.
Barometric (BARO) pressure is 70 kPa or more.
Engine speed is less than 1200 RPM.
Fuel level is between 15-85 percent.
DTC P0440 diagnostic test has passed.
A vacuum decay condition, indicating a small leak, is detected during diagnostic test.