Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

Engine Hybrid System. Corolla. Zre142 Aze141
2Az-Fe Engine Control. Corolla. Zre142 Aze141

DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

COMPONENT OPERATING RANGE

MONITOR RESULT

CONFIRMATION DRIVING PATTERN

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

CHECK TERMINAL VOLTAGE (POWER SOURCE)

CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)

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

DTC P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

DTC P0038 Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2)

DTC P0141 Oxygen Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)


DESCRIPTION

Refer to DTC P0136 (Link).

HINT:
When any of these DTCs are stored, the ECM enters fail-safe mode. The ECM turns off the heated oxygen sensor heater in fail-safe mode. Fail-safe mode continues until the ignition switch is turned off.

Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)


DTC No.
DTC Detection Condition
Trouble Area
P0037
Heated oxygen sensor heater current is less than 0.3 A while the heater is operating (1 trip detection logic).
  1. Open in heated oxygen sensor (sensor 2) heater circuit
  2. Heated oxygen sensor (sensor 2)
  3. ECM
P0038
Heated oxygen sensor heater current is the specified value or more (1 trip detection logic).
  1. Short in heated oxygen sensor (sensor 2) heater circuit
  2. Heated oxygen sensor (sensor 2)
  3. ECM
P0141
Cumulative heater resistance correction value exceeds the acceptable threshold
(2 trip detection logic)
  1. Open or short in heated oxygen sensor (sensor 2) heater circuit
  2. Heated oxygen sensor (sensor 2)
  3. ECM

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.
  1. Heated Oxygen Sensor Heater Range Check (P0037 and P0038):
    1. The ECM monitors the current applied to the heated oxygen sensor heater to check the heater for malfunctions. If the current is below the threshold value, the ECM will determine that there is an open circuit in the heater. If the current is above the threshold value, the ECM will determine that there is a short circuit in the heater.
      1. Example:
        1. The ECM sets DTC P0038 when the current in the heated oxygen sensor heater is more than 2 A. Conversely, when the heater current is less than 0.3 A, DTC P0037 is set.
  1. Heated Oxygen Sensor Heater Performance (P0141):
    1. After the accumulated heater on time exceeds 100 seconds, the ECM calculates the heater resistance using 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


Related DTCs
P0037: Heated oxygen sensor (sensor 2) heater current (Low current)
P0038: Heated oxygen sensor (sensor 2) heater current (High current)
P0141: Heated oxygen sensor (sensor 2) heater performance
Required Sensors/Components (Main)
Heated oxygen sensor (sensor 2) heater
Required Sensors/Components (Related)
-
Frequency of Operation
Continuous: P0037, P0038
Once per driving cycle: P0141
Duration
0.2 seconds: P0038 (case 3)
0.5 seconds: P0037
1 second: P0038 (case 1 and case 2)
10 seconds: P0141
MIL Operation
Immediate: P0037, P0038
2 driving cycles: P0141
Sequence of Operation
None

TYPICAL ENABLING CONDITIONS


All
Monitor runs whenever following DTCs are not present
None

P0037
Battery voltage
10.5 to 20 V

P0038 (Case 1)
Battery voltage
10.5 V or more
Engine
Running
Starter
Off

P0038 (Case 2 and Case 3)
Battery voltage
10.5 to 20 V

P0141
Either of the following conditions is met:
Condition A or B
A. All of the following conditions are met:
Condition 1, 2, 3, 4, 5, 6 and 7
1. Air fuel ratio sensor (sensor 1) heater circuit fail (P0031, P0032)
Not detected
2. Heated oxygen sensor (sensor 2) heater circuit fail (P0037, P0038)
Not detected
3. Battery voltage
10.5 V or more
4. Fuel cut
Off
5. Time after fuel cut on to off
30 seconds or more
6. Accumulated heater on time
100 seconds or more
7. Learned heater off current operation completed fag
On
B. Duration that heated oxygen sensor impedance is less than 15 kΩ
2 seconds or more
HINT:
When the values for the Data List item O2 Heater Curr Val B1S2 is not 0 A, the heater is on.

TYPICAL MALFUNCTION THRESHOLDS


P0037
Heater current - Learned heater off current
Less than 0.3 A

P0038 (Case 1 and Case 2)
Learned heater off current
More than 2 A

P0038 (Case 3)
Heater current - Learned heater off current
2 A or more

P0141
Accumulated heater resistance
Varies with sensor element temperature (Example: More than 23 Ω)

COMPONENT OPERATING RANGE


Heated oxygen sensor heater current
0.3 to 2 A (when engine idles, heated oxygen sensor warmed up and battery voltage 11 to 14 V)

MONITOR RESULT

  1. Refer to Checking Monitor Status (COROLLA_ZRE142 RM000000PDR0CFX.html).

CONFIRMATION DRIVING PATTERN


Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for at least 30 seconds.
  5. Turn the ignition switch to ON and turn the Techstream on [A].
  6. Start the engine and idle it for 5 minutes or more [B].
  7. With the vehicle stationary, depress the accelerator pedal and maintain an engine speed of 3000 rpm for 1 minute [C].
  8. Idle the engine for 5 minutes or more [D].
  9. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [E].
  10. Read the pending DTCs.
    HINT:
    1. If a pending DTC is output, the system is malfunctioning.
    2. If a pending DTC is not output, perform the following procedure.
  11. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
  12. Input the DTC: P0037, P0038 or P0141.
  13. Check the DTC judgment result.

    Techstream Display
    		Description
    NORMAL
    1. DTC judgment completed
    2. System normal
    ABNORMAL
    1. DTC judgment completed
    2. System abnormal
    INCOMPLETE
    1. DTC judgment not completed
    2. Perform driving pattern after confirming DTC enabling conditions
    N/A
    1. Unable to perform DTC judgment
    2. Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit
    HINT:
    1. If the judgment result shows NORMAL, the system is normal.
    2. If the judgment result shows ABNORMAL, the system has a malfunction.
    3. If the judgment result shows INCOMPLETE or N/A, perform steps [B] through [E] again.
  14. If no pending DTC is output, perform a universal trip and check for permanent DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).
    HINT:
    1. If a permanent DTC is output, the system is malfunctioning.
    2. If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P0136 (COROLLA_ZRE142 RM000000WBY0H0X_08.html).

INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
  1. Sensor 1 refers to the sensor closest to the engine assembly.
  2. Sensor 2 refers to the sensor farthest away from the engine assembly.
  3. Refer to "Data List / Active Test" [O2 Heater B1S2 and O2 Heater Curr Val B1S2] (COROLLA_ZRE142 RM000000PDN0MIX.html).
  4. When the values for the Data List item O2 Heater Curr Val B1S2 is not 0 A, the heater is on.
  5. Read freeze frame data using the Techstream. 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.
  6. Change the fuel injection volume using the Control the Injection Volume function provided in the Active Test and monitor the heated oxygen sensor output voltage (COROLLA_ZRE142 RM000000WBY0H0X_10.html). If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.
1.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)

  1. Inspect the heated oxygen sensor (COROLLA_ZRE142 RM0000033D200QX.html).



NG
REPLACE HEATED OXYGEN SENSOR (COROLLA_ZRE142 RM0000033D300QX.html)
OK


2.CHECK TERMINAL VOLTAGE (POWER SOURCE)
Corolla. Zre142 Aze141.2Az-Fe Engine Control.Sfi System. Dtc P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2)

  1. Disconnect the heated oxygen sensor connector.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    B24-2 (+B) - Body ground
    		Ignition switch ON
    		11 to 14 V

  1. Reconnect the heated oxygen sensor connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (HEATED OXYGEN SENSOR - ENGINE ROOM RELAY BLOCK)
OK


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

  1. Disconnect the heated oxygen sensor connector.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    Tester Connection
    		Condition
    		Specified Condition
    B24-1 (HT1B) - B31-47 (HT1B)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):

    Tester Connection
    		Condition
    		Specified Condition
    B24-1 (HT1B) or B31-47 (HT1B) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the heated oxygen sensor connector.

  1. Reconnect the ECM connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (HEATED OXYGEN SENSOR - ECM)
OK


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

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Clear the DTCs (COROLLA_ZRE142 RM000000PDK0ZBX.html).

  1. Start the engine.

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

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

  1. Read DTCs.


Result:

Result
Proceed to
No output
A
P0037, P0038 or P0141
B


B
REPLACE ECM (COROLLA_ZRE142 RM000002WT402ZX.html)
A

CHECK FOR INTERMITTENT PROBLEMS (COROLLA_ZRE142 RM000000PDQ0VNX.html)