The powertrain control module detects a fault in the heater circuit of the upstream oxygen sensor on bank 2.
The heater inside the oxygen sensor can fail, preventing it from reaching operating temperature.
Damaged, corroded, or loose wiring between the sensor and PCM can interrupt heater power.
A protective fuse or relay in the heater circuit may have opened, cutting power to the sensor heater.
Corrosion or pins pushed out of the connector can cause high resistance or intermittent contact.
The internal driver that supplies voltage to the heater may have failed, though this is less common.
A complete PCM failure can affect heater control, but it is rarely the primary cause.
No. The heater circuit failure is almost always due to the sensor, its wiring, or a blown fuse, not the PCM itself.
You can usually drive short distances, but prolonged operation may cause increased emissions and reduced fuel economy.
Often it does, but if the wiring or fuse is faulty, the code will return even after a new sensor is installed.
Yes. A malfunctioning heater circuit can prevent the sensor from providing accurate readings, affecting emissions compliance.