SFI SYSTEM(w/o Canister Pump Module), Diagnostic DTC:P003012, P003013, P101A9E

DTC Code DTC Name
P003012 HO2S Heater Control Bank 1 Sensor 1 Circuit Short to Battery
P003013 HO2S Heater Control Bank 1 Sensor 1 Circuit Open
P101A9E A/F Sensor Heater Performance Bank 1 Sensor 1 Stuck On

DESCRIPTION

Refer to DTC P21951D.

Click here

Tech Tips


  • Although the DTC titles say oxygen sensor, these DTCs relate to the air fuel ratio sensor.

  • When any of these DTCs are stored, the ECM enters fail-safe mode. The ECM turns off the air fuel ratio sensor heater in fail-safe mode. Fail-safe mode continues until the power switch is turned off.

  • The ECM has a pulse width modulated control circuit to adjust the current through the heater. The air fuel ratio sensor heater circuit uses a relay on the +B side of the circuit.

    B006HB5E05
DTC No. Detection Item DTC Detection Condition Trouble Area MIL Memory Note
P003012 HO2S Heater Control Bank 1 Sensor 1 Circuit Short to Battery The air fuel ratio sensor heater current is the specified value or higher while the heater is operating (1 trip detection logic).

  • Short in air fuel ratio sensor (sensor 1) heater circuit

  • Air fuel ratio sensor (sensor 1)

  • ECM

 Comes on DTC stored SAE Code: P0032
P003013 HO2S Heater Control Bank 1 Sensor 1 Circuit Open The air fuel ratio sensor heater current is less than the specified value while the heater is operating (1 trip detection logic).

  • Open or short in air fuel ratio sensor (sensor 1) heater circuit

  • Air fuel ratio sensor (sensor 1)

  • ECM

 Comes on DTC stored SAE Code: P0031
P101A9E A/F Sensor Heater Performance Bank 1 Sensor 1 Stuck On The air fuel ratio sensor heater current is higher than the specified value while the heater is not operating (1 trip detection logic).

  • Short in air fuel ratio sensor (sensor 1) heater circuit

  • Air fuel ratio sensor (sensor 1)

  • ECM

 Comes on DTC stored SAE Code: P101D

MONITOR DESCRIPTION

The ECM uses information from the air fuel ratio sensor to regulate the air fuel ratio and keep it close to the stoichiometric air fuel ratio. This maximizes the ability of the three-way catalytic converter to purify the exhaust gases.

The air fuel ratio sensor detects oxygen levels in the exhaust gas and transmits the information to the ECM. The inner surface of the sensor element is exposed to the outside air. The outer surface of the sensor element is exposed to the exhaust gas. The sensor element is made of platinum-coated zirconia and includes an integrated heating element.

The zirconia element generates a small voltage when there is a large difference in the oxygen concentrations between the exhaust gas and outside air. The platinum coating amplifies this voltage generation.

The air fuel ratio sensor is more efficient when heated. When the exhaust gas temperature is low, the sensor cannot generate a useful voltage without supplementary heating. The ECM regulates the supplementary heating using a duty-cycle approach to adjust the average current in the sensor heater element. If the heater current is outside the normal range, the signal transmitted by the air fuel ratio sensor becomes inaccurate. As a result, the ECM is unable to regulate the air fuel ratio properly.

When the current in the air fuel ratio sensor heater is outside the normal operating range, the ECM interprets this as a malfunction of the sensor heater and stores a DTC.

MONITOR STRATEGY

Required Sensors/Components Air fuel ratio sensor (sensor 1) heater
Frequency of Operation Continuous

TYPICAL ENABLING CONDITIONS

P003012
Output duty cycle Higher than 0%
P003013
Output duty cycle 30% or higher
P101A9E
Output duty cycle Less than 60%

CONFIRMATION DRIVING PATTERN

B006I78E76

  1. Connect the GTS to the DLC3.

  2. Turn the power switch on (IG).

  3. Turn the GTS on.

  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).

  5. Turn the power switch off and wait for at least 30 seconds.

  6. Turn the power switch on (IG) [A].

  7. Turn the GTS on.

  8. Put the engine in Inspection Mode (Maintenance Mode).

    Click here

  9. Start the engine and idle it for 5 minutes or more [B].

  10. With the vehicle stationary, depress the accelerator pedal and maintain an engine speed of 2500 rpm for 1 minute [C].

    Tech Tips

    During charge control, the engine speed is set at idle. Therefore, the engine speed will not increase when the accelerator pedal is depressed. In this case, perform steps [C] and [D] after charge control has completed.

  11. Idle the engine for 5 minutes or more [D].

  12. Enter the following menus: Powertrain / Engine / Trouble Codes [E].

  13. Read the pending DTCs.

    Tech Tips


    • If a pending DTC is output, the system is malfunctioning.

    • If a pending DTC is not output, perform the following procedure.

  14. Enter the following menus: Powertrain / Engine / Utility / All Readiness.

  15. Input the DTC: P003012, P003013 or P101A9E.

  16. Check the DTC judgment result.

    GTS Display Description
    NORMAL

    • DTC judgment completed

    • System normal
    ABNORMAL

    • DTC judgment completed

    • System abnormal
    INCOMPLETE

    • DTC judgment not completed

    • Perform driving pattern after confirming DTC enabling conditions
    N/A

    • Unable to perform DTC judgment

    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    Tech Tips


    • If the judgment result is NORMAL, the system is normal.

    • If the judgment result is ABNORMAL, the system is malfunctioning.

    • If the judgment result is INCOMPLETE or N/A, perform steps [B] through [E] again.

WIRING DIAGRAM

Refer to DTC P21951D.

Click here

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following procedure.

Tech Tips


  • The operation of the air fuel ratio sensor heater can be checked by referring to the Data List item A/F (O2) Sensor Heater Duty Ratio B1S1.

    Click here

  • Sensor 1 refers to the sensor closest to the engine assembly.

  • Sensor 2 refers to the sensor farthest away from the engine assembly.

  • Change the fuel injection volume using the Active Test "Control the Injection Volume for A/F Sensor" and monitor the air fuel ratio sensor output voltage Click here. If the air fuel ratio sensor output voltage does not change (almost no reaction) while performing the Active Test, the air fuel ratio sensor may be malfunctioning.

  • Read freeze frame data using the GTS. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE


  1. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)


    1. Inspect the air fuel ratio sensor.

      Click here

      Tech Tips

      Perform "Inspection After Repair" after replacing the air fuel ratio sensor.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIR FUEL RATIO SENSOR Click here

    OK

  2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF AIR FUEL RATIO SENSOR)

    B006HGRC27
    *a

    Front view of wire harness connector

    (to Air Fuel Ratio Sensor)

    1. Disconnect the air fuel ratio sensor connector.

    2. Turn the power switch on (IG).

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      C24-2 (+B) - Body ground Power switch on (IG) 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (NO. 1 INTEGRATION RELAY - AIR FUEL RATIO SENSOR)

    OK

  3. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)


    1. Disconnect the air fuel ratio sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      C24-1 (HA1A) - C31-27 (HA1A) Always Below 1 Ω
      C24-1 (HA1A) or C31-27 (HA1A) - Body ground and other terminals Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CLEAR DTC


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    3. Turn the GTS on.

    4. Clear the DTCs.


      Powertrain > Engine > Clear DTCs

    5. Turn the power switch off and wait for at least 30 seconds.

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK WHETHER DTC OUTPUT RECURS (DTC P003012, P003013 OR P101A9E)


    1. Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.

    2. Enter the following menus: Powertrain / Engine / Trouble Codes.

    3. Read the DTCs.


      Powertrain > Engine > Trouble Codes
      Result
      Result Proceed to
      DTCs are not output A
      DTC P003012, P003013 or P101A9E is output B

    A

    CHECK FOR INTERMITTENT PROBLEMS Click here

    B

    REPLACE ECM Click here