Intake Air Temperature Sensor
- A malfunction in Intake Air Temperature (IAT) sensor circuit can set a DTC. For testing procedures and specifications, perform appropriate diagnostic test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS
in SELF-DIAGNOSTICS - 3.2L CTS article. An out-of-calibration IAT sensor may not set a DTC. Use the following procedure to test sensor calibration.
- Disconnect IAT sensor harness connector. See COMPONENT LOCATIONS
. Using DVOM, measure resistance of IAT sensor at specified temperatures. See Fig 1
. Resistance should be high when air temperature is cold and drop as air temperature warms. With vehicle sitting overnight, ECT sensor and IAT sensor should have close to the same resistance reading. If resistance is not within specification, replace IAT sensor. See INTAKE AIR TEMPERATURE SENSOR
under SENSORS in REMOVAL & INSTALLATION article.
Courtesy of GENERAL MOTORS CORP.