Search OBD-II codes
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15 codes found with 1 filter applied
Showing 1–15 of 15
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HO2S heater control circuit — Bank 1 Sensor 1
The upstream O2 sensor heater control circuit has a fault.
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HO2S heater control circuit low — Bank 1 Sensor 1
The O2 sensor heater circuit reads too low.
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Oxygen sensor circuit malfunction — Bank 1 Sensor 1
The upstream oxygen sensor circuit has a fault.
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Oxygen sensor circuit low voltage — Bank 1 Sensor 1
The upstream oxygen sensor voltage is stuck low, indicating a very lean signal or sensor fault.
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O2 sensor slow response — Bank 1 Sensor 1
The upstream oxygen sensor responds too slowly.
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Oxygen sensor no activity detected — Bank 1 Sensor 1
The upstream oxygen sensor never changes voltage — no signal activity.
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Oxygen sensor heater circuit malfunction — Bank 1 Sensor 1
The O2 sensor heater is not working, slowing warm-up and risking emissions failure.
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O2 sensor circuit malfunction — Bank 1 Sensor 2
The downstream oxygen sensor circuit has a fault.
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O2 sensor circuit low voltage — Bank 1 Sensor 2
The downstream O2 sensor voltage is too low.
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Oxygen sensor heater circuit malfunction — Bank 1 Sensor 2
The downstream O2 sensor heater circuit has a fault.
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Oxygen sensor circuit malfunction — Bank 2 Sensor 1
The bank 2 upstream oxygen sensor circuit has a fault.
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O2 sensor heater circuit — Bank 2 Sensor 2
The bank 2 downstream O2 sensor heater has a fault.
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Secondary air injection system incorrect flow
The secondary air injection is not delivering the expected airflow.
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Catalyst system efficiency below threshold — Bank 1
The downstream O2 sensor sees too little catalyst activity. Confirm the converter is really bad before replacing it.
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Catalyst efficiency below threshold — Bank 2
The bank 2 catalyst is below efficiency threshold.