1ZR-FE ENGINE CONTROL SFI SYSTEM P0037 Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2) P0038 Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2) P102D O2 Sensor Heater Circuit Performance Bank 1 Sensor 2 Stuck ON
DESCRIPTION
Refer to DTC P0137.
Click hereEngine / Hybrid System>1ZR-FE ENGINE CONTROL>SFI SYSTEM>P0137
- 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.
·The heated oxygen sensor heater circuit uses a relay on the +B side of the circuit.
0.115,0.115 2.885,0.323 2.771,0.208 10 Reference (System Diagram of Sensor 2): 0.156,1.083 1.042,1.323 0.885,0.24 10 from Battery 1.115,1.26 2,1.5 0.885,0.24 10 EFI-MAIN 2.115,2.375 3,2.615 0.885,0.24 10 EFI-MAIN 2.927,1.271 3.604,1.49 0.677,0.219 10 EFI NO. 2 3.479,2.25 4.948,2.479 1.469,0.229 10 Heated Oxygen Sensor 3.844,1.875 4.396,2.156 0.552,0.281 10 Sensor 3.875,1.271 4.427,1.552 0.552,0.281 10 Heater 3.469,1.01 3.792,1.24 0.323,0.229 10 +B 4.51,1.563 4.948,1.781 0.438,0.219 10 OX1B 4.521,1 4.958,1.219 0.438,0.219 10 HT1B 3.458,1.563 3.698,1.813 0.24,0.25 10 E2 5.104,1.552 5.542,1.771 0.438,0.219 10 OX1B 5.115,0.99 5.552,1.208 0.438,0.219 10 HT1B 5.104,2.594 5.542,2.813 0.438,0.219 10 EX1B 5.833,3.49 6.271,3.708 0.438,0.219 10 ECM 5.115,2.979 5.552,3.198 0.438,0.219 10 MREL
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P0037 | Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2) | Heated oxygen sensor heater current is the specified value or less while the heater is operating (1 trip detection logic). | ·
Open in heated oxygen sensor (sensor 2) heater circuit ·
Heated oxygen sensor (sensor 2) ·
ECM |
Comes on | DTC stored |
| P0038 | Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2) | Heated oxygen sensor heater current reaches high limit (1 trip detection logic). | ·
Short in heated oxygen sensor (sensor 2) heater circuit ·
Heated oxygen sensor (sensor 2) ·
ECM |
Comes on | DTC stored |
| P102D | O2 Sensor Heater Circuit Performance Bank 1 Sensor 2 Stuck ON | Heated oxygen sensor heater current is higher than the specified value while the heater is not operating (1 trip detection logic). | ECM | Comes on | DTC stored |
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.
MONITOR STRATEGY
| Frequency of Operation | Continuous |
TYPICAL ENABLING CONDITIONS
| Time after heater on | 10 seconds or more |
| Time after heater on | 10 seconds or more |
| Time after heater on | 10 seconds or more |
CONFIRMATION DRIVING PATTERN
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON and turn the GTS on [A].
Start the engine and idle it for 5 minutes or more [B].
With the vehicle stationary, depress the accelerator pedal and maintain an engine speed of 3000 rpm for 1 minute [C].
Idle the engine for 5 minutes or more [D].
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [E].
Read the pending DTCs.
- HINT:
- ·
If a pending DTC is output, the system is malfunctioning.
·If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC: P0037, P0038 or P102D.
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 |
- HINT:
- ·
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.
WIRING DIAGRAM
Refer to DTC P0137.
Click hereEngine / Hybrid System>1ZR-FE ENGINE CONTROL>SFI SYSTEM>P0137
CAUTION / NOTICE / HINT
- NOTICE:
-
Inspect the fuses for circuits related to this system before performing the following procedure.
- HINT:
- ·
Sensor 1 refers to the sensor closest to the engine assembly.
·Sensor 2 refers to the sensor farthest away from the engine assembly.
·Refer to "Data List / Active Test" [O2 Heater B1S2 and O2 Heater Curr Val B1S2].
Click hereEngine / Hybrid System>1ZR-FE ENGINE CONTROL>SFI SYSTEM>DATA LIST / ACTIVE TEST
·When the values for the Data List item O2 Heater Curr Val B1S2 is not 0 A, the heater is on.
·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.
·Change the fuel injection volume using the Control the Injection Volume for A/F Sensor function provided in the Active Test and monitor the heated oxygen sensor output voltage (Click hereEngine / Hybrid System>1ZR-FE ENGINE CONTROL>SFI SYSTEM>P0137). If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.
PROCEDURE
Inspect the heated oxygen sensor.
Click hereEngine / Hybrid System>1ZR-FE ENGINE CONTROL>HEATED OXYGEN SENSOR>INSPECTION
- Result:
Proceed to OK NG
OK
NG
| *a | Front view of wire harness connector
(to Heated Oxygen Sensor) |
Disconnect the heated oxygen sensor connector.
Turn the ignition switch to ON.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection Condition Specified Condition E36-2 (+B) - Body ground Ignition switch ON 11 to 14 V
- Result:
Proceed to OK NG
OK
NG
Disconnect the heated oxygen sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection Condition Specified Condition E36-1 (HT1B) - B56-63 (HT1B) Always Below 1 Ω E36-1 (HT1B) or B56-63 (HT1B) - Body ground Always 10 kΩ or higher
- Result:
Proceed to OK NG
OK
NG
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
- Powertrain > Engine and ECT > Clear DTCs
- 50002 234
Turn the ignition switch off and wait for at least 30 seconds.
Turn the ignition switch to ON.
Turn the GTS on.
Drive the vehicle in accordance with the driving pattern described in Confirmation Driving Pattern.
Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
Read the pending DTCs.
- Powertrain > Engine and ECT > Trouble Codes
- 50001 234
- Result:
Result Proceed to DTCs are not output A DTC P0037, P0038 or P102D is output B
A
B