Conditions for Running the DTC

Before the ECM can report DTC P0446 failed, DTCs P0450, P0451, P0452, and P0453 must run and pass.
DTC P0100, P0101, P0102, P0103, P0111, P0112, P0113, P0116, P0117, P0118, P0119, P0121, P0122, P0123, P0128, P0221, P0222, P0223, P0443, P0449, P0451, P0452, P0453, P0458, P0459, P0496, P0497, P0498, P0499, P0560, P0562, P0563, P0700, P2122, P2123, P2127, P2128 or P2138 is not set.
The ignition voltage is 10-18 volts.
The Closed Loop fuel control is enabled.
The engine run time is greater than 10 minutes or the fuel trim is stable.
The engine is idling.
The FTP is between -18.7 and +9.8 mm Hg (-10.0 and +5.2 in. H2O).
The ambient air temperature (AAT) is between 2-32°C (35-90°F).
The ECT and the IAT are within 10°C (18°F) of each other at engine start-up.
The barometric pressure (BARO) is greater than 68 kPa.
The long term fuel trim remains steady, less than 3 percent change in 200 ms over a period of 8 seconds.
The fuel level is between 11-88 percent.
The vehicle speed sensor (VSS) is less than 3 km/h (2 mph).
The above conditions exist for greater than 5 seconds.
DTC P0446 will attempt to run up to 10 times or until the test completes successfully once per ignition cycle.