Reference meaning
What does this code mean?
The wording below belongs to the named make and communication. Match the complete code, reporting module, model year and engine before applying it.
A code identifies a detected condition, not a part that must automatically be replaced.
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Record codes and freeze-frame data. Check battery condition, related codes and visible wiring or hose damage. Follow the vehicle's diagnostic procedure and test results before replacing parts.
Scan worksheet →Manufacturer wording
Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
P0138O2 Sensor 1/2 Circuit High
P0138Rear Secondary Heated Oxygen Sensor Circuit High Voltage
P0138O2 Sensor Circuit High Voltage Bank 1 Sensor 2
Manufacturer communications
72Original wording in English
JEEP
Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P0301 - Cylinder 1 Misfire (Active or Stored status set during cold start catalyst heating). ● P0302 …
JEEP
Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P08A6 - Gear Lever Position Sensor System – Multiple Sensor Correlation (Manual Transmission Only). ● P…
JEEP
Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● **P08A6 – Gear Lever Position Sensor System – Multiple Sensor Correlation (Manual Transmission Only). ● P152F – …
SUBARU
"This bulletin announces the availability of new oxygen sensors developed to address the following Diagnostic Trouble Codes (DTCs) detected by the Engine Control Module: • P0137: O2 Sensor Circuit Low Voltage Bank 1 Sensor 2 • P0138: O2 Sensor Circuit High Voltage Bank 1 Sensor 2 • P0140: O2 Sensor Circuit No Activity Detected B…
Check vehicle applicability
171A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Code meaning and manufacturer information
Original wording in English · Historical directory labels; manufacturer applicability has not been established for every entry.
O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)
Can I keep driving?
A code alone cannot establish whether driving is safe. A flashing malfunction light, severe shaking, overheating, oil-pressure warning or loss of braking or steering needs prompt attention. Stop in a safe place and seek assistance when control or engine safety is affected. Follow the vehicle handbook.