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Home >> Alfa Romeo >> 2017 >> Giulia Base, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> 2.0L - DTCS P0480-00 To P0687-00 >> DTC Troubleshooting >> P0605-00-Internal Control Module Read Only Memory (ROM) Error >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. Turn the ignition on.
    2. With the scan tool, erase DTCs in the PCM.
    3. Cycle the ignition off and back to on.
    4. With the scan tool, read DTCs.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK FOR ANY SERVICE BULLETINS OR PCM SOFTWARE UPDATES THAT APPLY 
    1. Before proceeding with this test procedure, perform any Service Bulletins that relate to this fault code.
    2. With the scan tool, read and record the PCM part number.
    3. Verify the Powertrain Control Module (PCM) is at the latest calibration (flash level). If not at the latest flash level, update the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to POWERTRAIN VERIFICATION TEST .
    4. Cycle the ignition off and back to on.
    5. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Go To  3

      No 

  3. 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 .