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Home >> Alfa Romeo >> 2019 >> Giulia Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> 2.0L - DTCS B1810-00 To P0111-00 >> DTC Troubleshooting >> P0038-00-Ho2S Heater Control Circuit High Bank 1 Sensor 2 >> Diagnostic Test

Diagnostic Test

  1. CHECK FOR ANY SERVICE BULLETINS OR PCM SOFTWARE UPDATES 
    1. Check for any applicable Service Bulletins or Flash updates related to the DTC.

      Are there any applicable Service Bulletins or Flash updates?

      Yes 

      No 

      • Go To  2
  2. READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN 
    1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
    2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
    3. With the scan tool, erase all DTCs.
    4. Turn the ignition off for a minimum of 10.0 seconds.
    5. Turn the ignition on.
    6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Go To  3

      No 

  3. CHECK THE (K299) O2 SENSOR 1/2 HEATER CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Disconnect the Oxygen Sensor 1/2 harness connector.
    3. Disconnect the PCM C1 harness connector.
    4. Measure the resistance of the (K299) O2 Sensor 1/2 Heater Control circuit between the Oxygen Sensor 1/2 harness connector and the PCM C1 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  4

      No 

      • Repair the (K299) O2 Sensor 1/2 Heater Control circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  4. CHECK THE (Z101) O2 SENSOR HEATER GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Measure the resistance between ground and the (Z101) O2 Sensor Heater Ground circuit at the O2 Sensor 1/2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  5

      No 

      • Repair the (Z101) O2 Sensor Heater Ground circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK THE (K299) O2 1/2 HEATER CONTROL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT 
    1. Check for continuity between the (K299) O2 Sensor 1/2 Heater Control circuit and all other circuits at the PCM C1 harness connector.

      Is there continuity between the (K299) O2 Sensor 1/2 Heater Control circuit and any other circuit?

      Yes 

      • Repair the (K299) O2 Sensor 1/2 Heater Control circuit for a short to the circuit that showed continuity.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  6
  6. CHECK THE PCM HEATER CONTROL DRIVER FOR PROPER OPERATION 
    1. Reconnect the PCM C1 harness connector.
    2. Turn the ignition on.
    3. With the scan tool, actuate the Oxygen Sensor 1/2 Heater Control to the maximum allowable percentage.
    4. Using a 12-volt test light connected to ground, probe the (K299) O2 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.
      NOTE:

      The test light should be illuminated. The brightness will be dependent on the actuation percentage selected.

    5. With the scan tool, actuate the Oxygen Sensor 1/2 control to the OFF (0%) position.
    6. Using a 12-volt test light connected to ground, probe the (K299) O2 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.
      NOTE:

      The test light should not be illuminated.

      Does the test light illuminate with the actuator ON (25%) and not illuminated with the actuator OFF (0%)?

      Yes 

      No 

      • Go To  7
  7. 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 

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