Mike's Workshop Manuals: Service manuals for every vehicle
Home >> Chevrolet >> 2001 >> Prizm Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 1.8L >> Diagnostic Tests >> DTC P0110: IAT Sensor Circuit >> Diagnostic Procedures

Diagnostic Procedures

  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
  2. Using scan tool, monitor IAT sensor parameter. If IAT sensor value is 284°F (140°C) or greater, go to step  5. If IAT sensor value is less than 284°F (140°C), go to next step.
  3. Using scan tool, monitor IAT sensor parameter. If IAT sensor value is -40°F (-40°C) or less, go to step  7. If IAT sensor value is greater than -40°F (-40°C), go to next step.
  4. Using scan tool, clear DTC information and place vehicle into check mode. Operate vehicle within FREEZE FRAME conditions. If DTC resets, go to step  2. If DTC does not reset, see DIAGNOSTIC AIDS .
  5. Turn ignition off. Disconnect IAT sensor harness connector (IAT sensor is part of MAF sensor and is located in air cleaner box cover). Turn ignition on, with engine off. Using scan tool, monitor IAT sensor parameter. If IAT sensor value is -40°F (-40°C), go to step  13. If IAT sensor value is not -40°F (-40°C), go to next step.
  6. Turn ignition off. Disconnect PCM harness connector. Check for short to ground or ground circuit in Yellow/Black wire between IAT sensor and PCM harness connector C2 terminal No. 22 for 4-speed A/T or No. 3 for except 4-speed A/T. See Figure or Figure . Repair as necessary. After repairs, go to step  15. If circuit is okay, go to step  14.
  7. Disconnect IAT sensor harness connector. Using a fused jumper wire, jumper IAT sensor harness connector terminal No. 4 (Yellow/Black wire) and No. 5 (Brown wire). See Figure. Using scan tool, monitor IAT sensor parameter. If IAT sensor value is 284°F (140°C) or greater, go to step  9. If IAT sensor value is less than 284°F (140°C), go to next step.
  8. Using a fused jumper wire, jumper IAT sensor harness connector terminal No. 5 (Brown wire) to ground. Using scan tool, monitor IAT sensor parameter. If IAT sensor value is 284°F (140°C) or greater, go to step  10. If IAT sensor value is less than 284°F (140°C), go to step  11.
  9. Turn ignition off. Check for poor connections at IAT sensor connector. Repair as necessary. After repairs, go to step  15. If connections are okay, go to step  13.
  10. Turn ignition off. Disconnect PCM harness connector. Check for open in Brown wire between IAT sensor and PCM harness connector. Repair as necessary. After repairs, go to step  15. If circuit is okay, go to step  12.
  11. Turn ignition off. Disconnect PCM harness connector. Check for open or short in Yellow/Black wire to PCM harness connector. Repair as necessary. After repairs, go to step  15. If circuit is okay, go to next step.
  12. Check for poor connections at PCM. Repair as necessary. After repairs, go to step  15. If connections are okay, go to step  14.
  13. Turn ignition off. Replace IAT/MAF sensor assembly. After replacing sensor, go to step  15.
  14. Replace PCM. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  15. Turn ignition on, with engine off. Using scan tool, clear DTC information. Road test vehicle within conditions for running DTC. See CODE ENABLE CRITERIA . Check for DTCs. If no DTCs are stored, repair is complete. If any DTCs are stored, diagnose affected DTCs.
scientia non olet · About Mike's Workshop Manuals