DTC P0030-12: HO2S Heater Control Bank 1 Sensor 1 Circuit Short to Battery; DTC P0030-13: HO2S Heater Control Bank 1 Sensor 1 Circuit Open; DTC P101A-9E: A/F Sensor Heater Performance Bank 1 Sensor 1 Stuck On [10/2022 - 11/2023]: Description
The air fuel ratio sensor (sensor 1) generates current that corresponds to the actual air fuel ratio. This sensor current is used to provide the ECM with feedback so that it can control the air fuel ratio. The ECM determines the deviation from the stoichiometric air fuel ratio level, and regulates the fuel injection duration. If the air fuel ratio sensor (sensor 1) malfunctions, the ECM is unable to control the air fuel ratio accurately.
The air fuel ratio sensor (sensor 1) is a planar type sensor and integrated with the heater, which heats the solid electrolyte (zirconia element). This heater is controlled by the ECM. When the intake air volume is low (the exhaust gas temperature is low), a current flows into the heater to heat the sensor, in order to facilitate accurate oxygen concentration detection. In addition, the sensor and heater portions are a narrow type. The heat generated by the heater is conducted to the solid electrolyte through the alumina, therefore sensor activation is accelerated.
In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a three-way catalytic converter is used. For the most efficient use of the three-way catalytic converter, the air fuel ratio must be precisely controlled so that it is always close to the stoichiometric level.
HINT:
- When any of these DTCs are stored, the ECM enters fail-safe mode. The ECM turns off the air fuel ratio sensor (sensor 1) heater in fail-safe mode. Fail-safe mode continues until the ignition switch is turned off.
- Although the DTC titles say oxygen sensor, these DTCs relate to the air fuel ratio sensor (sensor 1).
- The ECM has a pulse width modulated control circuit to adjust the current through the heater. The air fuel ratio sensor (sensor 1) heater circuit uses a relay on the +B side of the circuit.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory | Note |
|---|---|---|---|---|---|---|
| P0030-12 | HO2S Heater Control Bank 1 Sensor 1 Circuit Short to Battery | The air fuel ratio sensor (sensor 1) heater current is more than the specified value while the heater is operating (1 trip detection logic). |
|
Comes on | DTC stored |
|
| P0030-13 | HO2S Heater Control Bank 1 Sensor 1 Circuit Open | The air fuel ratio sensor (sensor 1) heater current is less than the specified value while the heater is operating (1 trip detection logic). |
|
Comes on | DTC stored |
|
| P101A-9E | A/F Sensor Heater Performance Bank 1 Sensor 1 Stuck On | The air fuel ratio sensor (sensor 1) heater voltage level is low while the heater is not operating (1 trip detection logic). |
|
Comes on | DTC stored |
|