| DTC Code | DTC Name |
|---|---|
| P0037 | Oxygen Sensor Heater Control Circuit Low (Bank 1 Sensor 2) |
| P0038 | Oxygen Sensor Heater Control Circuit High (Bank 1 Sensor 2) |
| P0057 | Oxygen Sensor Heater Control Circuit Low (Bank 2 Sensor 2) |
| P0058 | Oxygen Sensor Heater Control Circuit High (Bank 2 Sensor 2) |
| P102D | O2 Sensor Heater Circuit Performance Bank 1 Sensor 2 Stuck ON |
| P105D | O2 Sensor Heater Circuit Performance Bank 2 Sensor 2 Stuck ON |
DESCRIPTION
Refer to DTC P0136 Click here.
Tech Tips
Sensor 2 refers to the sensor mounted behind the Three-Way Catalytic Converter (TWC) and located far from the engine assembly.
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. The ECM continues operating in fail-safe mode until the engine switch is turned off.
The ECM provides a pulse-width modulated control circuit to adjust the current through the heater. The heated oxygen sensor heater circuit uses a relay on the +B side of the circuit.
| DTC No. | DTC Detection Condition | Trouble Area |
|---|---|---|
| P0037 P0057 |
The heated oxygen sensor heater (bank 1, 2 sensor 2) current is below 0.3 A (1 trip detection logic). |
|
| P0038 P0058 |
The heated oxygen sensor (bank 1, 2 sensor 2) current is higher than 2 A (1 trip detection logic). |
|
| P102D P105D |
The heated oxygen sensor heater (bank 1, 2 sensor 2) current is higher than a specified value while the heater is not operating (1 trip detection logic). | ECM |
Tech Tips
Bank 1 refers to the bank that includes the No. 1 cylinder.
Bank 2 refers to the bank that does not include the No. 1 cylinder.
Sensor 1 refers to the sensor closest to the engine assembly.
Sensor 2 refers to the sensor farthest away from the engine assembly.
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.
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 and stores a DTC.
WIRING DIAGRAM
Refer to DTC P0136 Click here.
CAUTION / NOTICE / HINT
Note
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
Tech Tips
Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. 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
INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)
Inspect the heated oxygen sensor Click here.
| NG |
|
REPLACE HEATED OXYGEN SENSOR Click here |
| OK |
|
CHECK TERMINAL VOLTAGE (+B OF HEATED OXYGEN SENSOR)
| *A | for Manual Transmission |
| *B | for Automatic Transmission |
| *a | Front view of wire harness connector (to Heated Oxygen Sensor Bank 1) |
| *b | Front view of wire harness connector (to Heated Oxygen Sensor Bank 2) |
| *c | Front view of wire harness connector (to Heated Oxygen Sensor Bank 2) |
Disconnect the heated oxygen sensor connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
|
Reconnect the heated oxygen sensor connector.
| NG |
|
CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - NO. 1 INTEGRATION RELAY) Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)
Disconnect the heated oxygen sensor connector.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
|
| Standard Resistance (Check for Short) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
|
Reconnect the ECM connector.
Reconnect the heated oxygen sensor connector.
| OK |
|
REPLACE ECM Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - NO. 1 INTEGRATION RELAY)
Disconnect the heated oxygen sensor connector.
Remove the No. 1 integration relay from the engine room relay block.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance (Check for Open) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
|
| Standard Resistance (Check for Short) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
|||||||||
|
Reinstall the No. 1 integration relay.
Reconnect the heated oxygen sensor connector.
| OK |
|
CHECK ECM POWER SOURCE CIRCUIT Click here |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |