Inlet Air Temperature Switch

If code 44 is stored during cold weather operation, inlet air temperature switch should be tested. With ignition on and engine stopped, check Black/Red wire for open or ground. See Fig 1 .
If Black/Red wire is okay, check Black wire ground connection. If okay, check switch for continuity. Switch should have no continuity above 32°F (0°C). Switch should have continuity below 32°F (0°C).

Fig 1: Wiring Diagrams for Inlet Air Temperature Switch

Courtesy of GENERAL MOTORS CORP.