SFI SYSTEM, Diagnostic DTC:P0037, P0038, P0141, P102D

DESCRIPTION

Refer to DTC P0136 Click here.

MONITOR DESCRIPTION

The sensing portion of the heated oxygen sensor has a zirconia element which is used to detect the oxygen concentration in the exhaust gas. If the zirconia element is at the appropriate temperature, and the difference between the oxygen concentrations surrounding the inside and outside surfaces of the sensor is large, the zirconia element generates voltage signals. In order to increase the oxygen concentration detecting capacity of the zirconia element, the ECM supplements the heat from the exhaust with heat from a heating element inside the sensor.

Heated Oxygen Sensor Heater Range Check (P0037, P0038 and P102D):

• The ECM monitors the current applied to the heated oxygen sensor heater to check the heater for malfunctions.

  If the heater current is outside the normal range, the signal transmitted by the heated oxygen sensor becomes inaccurate. When the current in the heated oxygen sensor heater is outside the normal operating range, the ECM interprets this as a malfunction in the sensor heater and stores a DTC.

Heated Oxygen Sensor Heater Performance (P0141):

• After the accumulated heater on time exceeds 100 seconds, the ECM calculates the heater resistance using auxiliary battery voltage and the current applied to the heater. If the resistance is above the threshold value, the ECM determines that there is a malfunction in the heated oxygen sensor heater and stores DTC P0141.

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

MONITOR RESULT

Refer to detailed information in Checking Monitor Status Click here.

CONFIRMATION DRIVING PATTERN

1. Connect the Techstream to the DLC3.

2. Turn the power switch on (IG) and turn the Techstream on.

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

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

5. Turn the power switch on (IG) and turn the Techstream on [A].

6. Put the engine in inspection mode (maintenance mode) Click here.

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

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

   Tech Tips

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

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

10. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [E].

11. 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.

12. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

13. Input the DTC: P0037, P0038, P0141 or P102D.

14. Check the DTC judgment result.

    Techstream 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 shows NORMAL, the system is normal.

    • If the judgment result shows ABNORMAL, the system has a malfunction.

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

15. If no pending DTC is output, perform a universal trip and check for permanent DTCs Click here.

    Tech Tips

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

    • If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

   1. Inspect the heated oxygen sensor Click here.

   NG

   REPLACE HEATED OXYGEN SENSOR Click here

   OK

2. CHECK TERMINAL VOLTAGE (POWER SOURCE OF HEATED OXYGEN SENSOR)

   1. Disconnect the heated oxygen 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 E21-2 (+B) - Body ground Power switch on (IG) 11 to 14 V

      Text in Illustration

      *a	Front view of wire harness connector (to Heated Oxygen Sensor)

   NG

   CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - NO. 1 INTEGRATION RELAY) Click here

   OK

3. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)

   1. Disconnect the heated oxygen 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 E21-1 (HT1B) - E28-24 (HT1B) Always Below 1 Ω E21-1 (HT1B) or E28-24 (HT1B) - Body ground Always 10 kΩ or higher

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK WHETHER DTC OUTPUT RECURS (DTC P0037, P0038, P0141 OR P102D)

   1. Connect the Techstream to the DLC3.

   2. Turn the power switch on (IG).

   3. Turn the Techstream on.

   4. Clear the DTCs Click here.

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

   6. Turn the power switch on (IG).

   7. Turn the Techstream on.

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

   9. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.

   10. Read the pending DTCs.

       Result

       Result	Proceed to
       DTC is not output	A
       DTC P0037, P0038, P0141 or P102D is output	B

   B

   REPLACE ECM Click here

   A

   CHECK FOR INTERMITTENT PROBLEMS Click here

5. CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - NO. 1 INTEGRATION RELAY)

   1. Disconnect the heated oxygen sensor connector.

   2. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition E21-2 (+B) - 1A-6 Always Below 1 Ω E21-2 (+B) or 1A-6 - Body ground Always 10 kΩ or higher

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

6. CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY)

   1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

      

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

      Standard Voltage
      Tester Connection Condition Specified Condition 1D-1 - Body ground Always 11 to 14 V

      Text in Illustration

      *a	Front view of wire harness connector (to No. 1 Integration Relay)

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - NO. 1 INTEGRATION RELAY)

   OK

   REPLACE NO. 1 INTEGRATION RELAY Click here