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DTC P0030

DTC P0030 A/F sensor heater control circuit problem
DETECTION CONDITION 
  • The PCM monitors the A/F sensor impedance when under the A/F sensor heater control for 190 s.  If the impedance is more than 44 ohms  while PCM turns A/F sensor heater on, the PCM determines that there is a A/F sensor heater control circuit problem.

Diagnostic support note 
  • This is a continuous monitor (A/F sensor heater, HO2S heater).
  • The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
  • PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • A/F sensor connector or terminals malfunction
  • A/F sensor heater malfunction
  • PCM connector or terminals malfunction
  • PCM malfunction
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED 
  • Have the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor heater, HO2S heater related) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 VERIFY RELATED PENDING CODE OR STORED DTC 
  • Turn the ignition switch off, then to the ON position (engine off).
  • Verify the related PENDING CODE or stored DTCs.
  • Are other DTCs present?
 Yes Go to the appropriate DTC inspection.
(See DTC TABLE ).
No Go to the next step.
4 INSPECT A/F SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the A/F sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 7.
No Go to the next step.
5 INSPECT A/F SENSOR HEATER 
 Yes Replace the A/F sensor, then go to Step 7.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION ).
No Go to the next step.
6 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to the next step.
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0030 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the DRIVE MODE 3.

    (See OBD-II DRIVE MODE ).

  • Is the PENDING CODE same as the DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
8 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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