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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A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
Before replacing a part
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.
P1621O2 Sensor Reference Voltage Circuit Low
P1621O2 Sensor Reference Voltage Circuit Low
Manufacturer communications
12Original wording in English
CHRYSLER, DODGE
Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the Powertrain Control Module (PCM) with the latest software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs…
CHRYSLER, DODGE
Flash: Powertrain Control Module (PCM) Updates This bulletin involves reprogramming the Powertrain Control Module (PCM) with the latest software. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs…
CHRYSLER, DODGE
Flash: 5.7L Diagnostic And System Improvements This bulletin involves reprogramming of the Powertrain Control Module (PCM) with the latest software. A small number of customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnosti…
CHRYSLER, DODGE
Flash: 5.7L Powertrain Diagnostic And System Enhancements This bulletin involves reprogramming the Powertrain Control Module (PCM) with the latest available software. A small number of customers may experience one or more of the following symptoms or a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the…
Check vehicle applicability
467A 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.
Control Module Long Term Memory Performance/ Immobilizer Code Words Do Not Match
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.