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Home >> Alfa Romeo >> 2019 >> Giulia Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> 2.0L - DTCS P0112-00 To P024B-00 >> DTC Troubleshooting >> P0112-00-Intake Air Temperature Sensor 1 Circuit Low >> Diagnostic Test

Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. With the scan tool, read Powertrain Control Module (PCM) DTCs and Freeze Frame Data and record on the repair order.
    2. Using the recorded Freeze Frame Data and the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
    3. With the scan tool, read DTCs.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK THE ABILITY OF THE PCM TO READ THE IAT SENSOR SIGNAL 
    1. Turn the ignition off.
    2. Disconnect the MAP Sensor harness connector.
    3. Turn the ignition on.
    4. With a scan tool, read DTCs.
      NOTE:

      The DTC P0113-00-INTAKE AIR TEMPERATURE SENSOR 1 CIRCUIT HIGH should be active or pending with the MAP Sensor harness connector unplugged.

      Does the scan tool display as described above?

      Yes 

      No 

      • Go To  3
  3. CHECK THE (K21) IAT SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Check for continuity between ground and the (K21) IAT Signal circuit at the MAP Sensor harness connector.

      Is there continuity between ground and the (K21) IAT Signal circuit?

      Yes 

      • Repair the (K21) IAT Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  4
  4. CHECK FOR THE (K21) IAT SIGNAL CIRCUIT SHORTED TO THE (K915) SENSOR GROUND CIRCUIT 
    1. Check for continuity between the (K21) IAT Signal circuit and the (K915) Sensor Ground circuit at the MAP Sensor harness connector.

      Is there continuity between the (K21) IAT Signal circuit and the (K915) Sensor Ground circuit?

      Yes 

      • Repair the short between the (K21) IAT Signal circuit and the (K915) Sensor Ground circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  5
  5. CHECK RELATED PCM AND COMPONENT CONNECTIONS 
    1. Perform any Service Bulletins that apply.
    2. Disconnect all PCM harness connectors.
    3. Disconnect all related in-line harness connections (if equipped).
    4. Disconnect the related component harness connectors.
    5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Check for spread terminals and verify proper terminal tension.

      Repair any conditions that are found.

    6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    9. With the scan tool, erase DTCs.
    10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    11. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      No 

      • The wiring or poor connection problem has been repaired.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .