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Home >> Alfa Romeo >> 2017 >> Giulia Base, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> 2.0L - DTCS P2237-00 To P2AE1-00 >> DTC Troubleshooting >> P2237-00-O2 Sensor Positive Current Control Circuit/Open >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE DTC 
    1. Turn the ignition on.
    2. With the scan tool, record then erase DTCs.
    3. Start the engine and road test until it reaches normal operating temperature.
    4. With the scan tool, read the pending, active or stored DTCs.

      Did any active or pending O2 Sensor DTCs return?

      Yes 

      • Go To  2

      No 

  2. CHECK THE (K89) O2 1/1 POSITIVE CURRENT CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Measure the resistance of the (K89) O2 1/1 Positive Current Control circuit between the O2 Sensor 1/1 harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  3

      No 

      • Repair the (K89) O2 1/1 Positive Current Control circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  3. REPLACE THE O2 SENSOR AND RETEST FOR DTCS 
    1. Reconnect the PCM C2 harness connector.
    2. Replace the O2 Sensor and reconnect the harness connector. Refer to SENSOR, OXYGEN, REMOVAL AND INSTALLATION .
    3. Turn the ignition on.
    4. With the scan tool, erase DTCs.
    5. Using the Freeze Frame Data or When Monitored Conditions above, operate the vehicle within the conditions that set the DTC.
    6. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Go To  4

      No 

  4. CHECK RELATED HARNESS CONNECTIONS 
    1. Disconnect all PCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. 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.

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