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.
Narrow by vehicle
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.
P1129Closed Loop Fueling Not Achieved - Bank 2 Upstream
P1129Closed Loop Fueling Not Achieved-Banks 2 Upstream
P1129closed loop fueling not achieved - Bank 2 Upstream
Manufacturer communications
22Original 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): ● **P0300 - Multiple Cylinder Misfire (Active or Stored status set during cold start catalyst heating). ●…
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): ● **P0300 - Multiple Cylinder Misfire (Active or Stored status set during cold start catalyst heating). ●…
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): ● **P0300 - Multiple Cylinder Misfire (Active or Stored status set during cold start catalyst heating). ●…
Check vehicle applicability
16A listed vehicle is a research lead. Confirm the engine, production range and software in the manufacturer's information.
| Make | Model | Model year |
|---|---|---|
| Acura | MDX ↗ | 2002 |
| Acura | MDX ↗ | 2001 |
| Ford | THUNDERBIRD ↗ | 2002 |
| Honda | ODYSSEY ↗ | 2003 |
| Honda | ODYSSEY ↗ | 2002 |
| Honda | ODYSSEY ↗ | 2001 |
| Honda | PILOT ↗ | 2003 |
| Jeep | COMMANDER ↗ | 2007 |
Code meaning and manufacturer information
Original wording in English · Historical directory labels; manufacturer applicability has not been established for every entry.
Downstream Heated O2 Sensors Swapped
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.