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Home >> Chevrolet >> 2003 >> Tracker 2D Utility, 4WD, Automatic >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 1 (Engine Control System Self-Diagnostics - 2.5L) >> Diagnostic Tests >> DTC P0111: IAT Sensor Performance >> Diagnostic Procedures
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Diagnostic Procedures

WARNING: This page is about a different variant/trim than selected.
  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check - engine controls, go to next step.
  2. Turn ignition off. Allow engine to cool to ambient air temperature. Turn ignition on, with engine off. Using scan tool, compare IAT sensor value with ambient air temperature. Is the IAT within 0-9°F (0-5°C) of ambient temperature? If yes, go to next step. If no, go to step  4 .
    3. NOTE: While performing this step, observe IAT sensor parameter on scan tool. Look for a skip, jump or no movement in IAT value while temperature increases or decreases.
  3. Disconnect the IAT sensor electrical connector. Remove the IAT sensor from the air cleaner assembly. Connect the IAT sensor electrical connector to the IAT sensor. Wrap a cool damp shop towel around the IAT sensor in order to lower the temperature while monitoring the IAT sensor parameter on the scan tool. Remove the cool shop towel and place a warm damp shop towel around the IAT sensor while monitoring the IAT sensor parameter on the scan tool. Did the scan tool indicate a skip, jump, or a fixed value in the IAT sensor display? If yes, go to step  9 . If no, see DIAGNOSTIC AIDS  .
  4. Disconnect the IAT sensor electrical connector. Jumper the harness side of the IAT sensor electrical connector with a fused jumper wire. Does the IAT equal 401°F (205°C)? If yes, go to step  9 . If no, go to next step.
  5. Remove the fused jumper wire. Disconnect the PCM electrical connector. Measure the resistance of the IAT sensor input circuit from the sensor to the PCM with a DVOM. Is the resistance less than 0.5 ohm? If yes, go to next step. If no, go to step  7 .
  6. Measure the resistance of the IAT sensor ground circuit from the sensor to the PCM with a DVOM. Is the resistance less than 0.5 ohm? If yes, go to step  10 . If no, go to step  8 .
  7. Repair the short to ground or high resistance in the IAT sensor input circuit between the PCM and the IAT sensor. After repairs, go to step  11 .
  8. Repair the open circuit or high resistance in the IAT sensor ground circuit between the PCM and the IAT sensor. After repairs, go to step  11 .
  9. Replace IAT sensor. After replacing sensor, go to step  11 .
  10. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  11. Turn ignition off. Remove DOME fuse for 30 seconds. Install DOME fuse. Reset radio clock time. Start engine. Operate the vehicle within the Conditions for Running the DTC or until the DTC P0111 diagnostic test has run. See CONDITIONS FOR RUNNING DTC  . Does the DTC run and pass? If yes, go to next step. If no, go to step  2 .
  12. With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no, system is okay.
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