Fuel System Codes
5,039 OBD-II diagnostic trouble codes in this category.
Showing page 35 of 51 (5,039 codes total)
| Code | Description | Subsystem | Severity |
|---|---|---|---|
| P23B5 | NOx Sensor Heater Sense Circuit Range/Performance Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23B6 | NOx Sensor Supply Voltage Circuit Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23B7 | NOx Sensor Heater Control Circuit Range/Performance Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23B8 | NOx Sensor Heater Sense Circuit Low Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23B9 | NOx Sensor Heater Sense Circuit High Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23BA | NOx Sensor Heater Sense Circuit Intermittent Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23BB | NOx Sensor Heater Resistance Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23BC | NOx Sensor Calibration Memory Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23BD | NOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23BE | NOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23BF | NOx Sensor Performance - Slow Response Low to High Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23C0 | NOx Sensor Performance - Slow Response High to Low Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23C1 | NOx Sensor Performance - Sensing Element Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23C2 | NOx Sensor Delayed Response - High to Low Bank 1 Sensor 3 | Fuel Metering | Medium |
| P23C3 | Engine Coolant Bypass Valve C Position Sensor Circuit | Fuel Metering | Medium |
| P23C4 | Engine Coolant Bypass Valve C Position Sensor Circuit Low | Fuel Metering | Medium |
| P23C5 | Engine Coolant Bypass Valve C Position Sensor Circuit High | Fuel Metering | Medium |
| P23C6 | Engine Coolant Bypass Valve C Control Circuit Driver Current/Temperature Too High | Fuel Metering | Medium |
| P23C7 | Fuel Heater Control Module Power Control Circuit/Open | Fuel Metering | Medium |
| P23C8 | Fuel Heater Control Module Power Control Circuit Low | Fuel Metering | Medium |
| P23C9 | Fuel Heater Control Module Power Control Circuit High | Fuel Metering | Medium |
| P23CA | Fuel Rail Heater Control Circuit/Open | Fuel Metering | Medium |
| P23CB | Fuel Rail Heater Control Circuit Low | Fuel Metering | Medium |
| P23CC | Fuel Rail Heater Control Circuit High | Fuel Metering | Medium |
| P23CD | Fuel Heater Control Module Feedback Signal/Open | Fuel Metering | Medium |
| P23CE | Fuel Heater Control Module Feedback Signal Performance | Fuel Metering | Medium |
| P23CF | Fuel Heater Control Module Feedback Signal Circuit Low | Fuel Metering | Medium |
| P23D0 | Fuel Heater Control Module Feedback Signal Circuit High | Fuel Metering | Medium |
| P23D1 | Cylinder 1 Fuel Heater Control Circuit/Open | Fuel Metering | Medium |
| P23D2 | Cylinder 1 Fuel Heater Control Circuit High | Fuel Metering | Medium |
| P23D3 | Cylinder 1 Fuel Heater Control Circuit Low | Fuel Metering | Medium |
| P23D4 | Cylinder 1 Fuel Heater Performance | Fuel Metering | Medium |
| P23D5 | Cylinder 2 Fuel Heater Control Circuit/Open | Fuel Metering | Medium |
| P23D6 | Cylinder 2 Fuel Heater Control Circuit High | Fuel Metering | Medium |
| P23D7 | Cylinder 2 Fuel Heater Control Circuit Low | Fuel Metering | Medium |
| P23D8 | Cylinder 2 Fuel Heater Performance | Fuel Metering | Medium |
| P23D9 | Cylinder 3 Fuel Heater Control Circuit/Open | Fuel Metering | Medium |
| P23DA | Cylinder 3 Fuel Heater Control Circuit High | Fuel Metering | Medium |
| P23DB | Cylinder 3 Fuel Heater Control Circuit Low | Fuel Metering | Medium |
| P23DC | Cylinder 3 Fuel Heater Performance | Fuel Metering | Medium |
| P23DD | Cylinder 4 Fuel Heater Control Circuit/Open | Fuel Metering | Medium |
| P23DE | Cylinder 4 Fuel Heater Control Circuit High | Fuel Metering | Medium |
| P23DF | Cylinder 4 Fuel Heater Control Circuit Low | Fuel Metering | Medium |
| P23E0 | Cylinder 4 Fuel Heater Performance | Fuel Metering | Medium |
| P23E1 | EGR C Control Circuit/Open | Fuel Injection | Medium |
| P23F2 | Cylinder 1 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F3 | Cylinder 2 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F4 | Cylinder 3 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F5 | Cylinder 4 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F6 | Cylinder 5 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F7 | Cylinder 6 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F8 | Cylinder 7 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23F9 | Cylinder 8 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23FA | Cylinder 9 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23FB | Cylinder 10 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23FC | Cylinder 11 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23FD | Cylinder 12 Injector B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23FE | Bank 1 System B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P23FF | Bank 2 System B Air-Fuel Ratio Imbalance | Fuel Metering | Medium |
| P240A | EVAP System Leak Detection Pump Heater Control Circuit/Open | Fuel Injection | Medium |
| P240B | EVAP System Leak Detection Pump Heater Control Circuit Low | Fuel Injection | Medium |
| P240C | EVAP System Leak Detection Pump Heater Control Circuit High | Fuel Injection | Medium |
| P240D | Alternative Fuel Low Pressure System Leak | Fuel Injection | Medium |
| P240E | Alternative Fuel High Pressure System Leak | Fuel Injection | Medium |
| P240F | EGR Slow Response | Fuel Injection | Medium |
| P241A | O2 Sensor Signals Swapped Bank 1 Sensor 1/Bank 1 Sensor 2 | Fuel Injection | Medium |
| P241B | O2 Sensor Signals Swapped Bank 2 Sensor 1/Bank 2 Sensor 2 | Fuel Injection | Medium |
| P241D | SCR Inducement - Forced Engine Shutdown | Fuel Injection | Medium |
| P241E | Reductant Heater Coolant Control Valve Stuck Closed | Fuel Injection | Medium |
| P241F | EGR Cooler B Efficiency Below Threshold | Fuel Injection | Medium |
| P242A | Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 3 | Fuel Injection | Medium |
| P242B | Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 1 Sensor 3 | Fuel Injection | Medium |
| P242C | Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 3 | Fuel Injection | Medium |
| P242D | Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 3 | Fuel Injection | Medium |
| P242E | Exhaust Gas Temperature Sensor Circuit Intermittent/Erratic Bank 1 Sensor 3 | Fuel Injection | Medium |
| P242F | Particulate Filter Restriction - Ash Accumulation Bank 1 | Fuel Injection | Medium |
| P243A | Particulate Filter Restriction - Ash Accumulation Bank 2 | Fuel Injection | Medium |
| P243B | Particulate Filter Restriction - Forced Limited Power Bank 2 | Fuel Injection | Medium |
| P243C | Particulate Filter Regeneration Frequency Bank 2 | Fuel Injection | Medium |
| P243D | Particulate Filter Regeneration Duration Bank 2 | Fuel Injection | Medium |
| P243E | Particulate Filter Regeneration Incomplete Bank 2 | Fuel Injection | Medium |
| P243F | Particulate Filter Restriction - Soot Accumulation Too High Bank 2 | Fuel Injection | Medium |
| P244A | Particulate Filter Differential Pressure Too Low Bank 1 | Fuel Injection | Medium |
| P244B | Particulate Filter Differential Pressure Too High Bank 1 | Fuel Injection | Medium |
| P244C | Exhaust Temperature Too Low For Particulate Filter Regeneration Bank 1 | Fuel Injection | Medium |
| P244D | Exhaust Temperature Too High For Particulate Filter Regeneration Bank 1 | Fuel Injection | Medium |
| P244E | Exhaust Temperature Too Low For Particulate Filter Regeneration Bank 2 | Fuel Injection | Medium |
| P244F | Exhaust Temperature Too High For Particulate Filter Regeneration Bank 2 | Fuel Injection | Medium |
| P245A | EGR Cooler Bypass Control Circuit/Open Bank 1 | Fuel Injection | Medium |
| P245B | EGR Cooler Bypass Control Circuit Range/Performance Bank 1 | Fuel Injection | Medium |
| P245C | EGR Cooler Bypass Control Circuit Low Bank 1 | Fuel Injection | Medium |
| P245D | EGR Cooler Bypass Control Circuit High Bank 1 | Fuel Injection | Medium |
| P245E | Particulate Filter Pressure Sensor B Circuit | Fuel Injection | Medium |
| P245F | Particulate Filter Pressure Sensor B Circuit Range/Performance | Fuel Injection | Medium |
| P246A | Exhaust Gas Temperature Sensor Circuit Intermittent/Erratic Bank 2 Sensor 3 | Fuel Injection | Medium |
| P246B | Vehicle Conditions Incorrect for Particulate Filter Regeneration | Fuel Injection | Medium |
| P246C | Particulate Filter Restriction - Forced Limited Power Bank 1 | Fuel Injection | Medium |
| P246D | Particulate Filter Pressure Sensor A/B Correlation | Fuel Injection | Medium |
| P246E | Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 4 | Fuel Injection | Medium |
| P246F | Exhaust Gas Temperature Sensor Circuit Range/Performance Bank 1 Sensor 4 | Fuel Injection | Medium |
About Fuel System Codes
This page lists all 5,039 OBD-II diagnostic trouble codes classified under the Fuel System category. These codes are stored by your vehicle's onboard computer when a sensor detects a malfunction in the fuel system system. Each code begins with a letter indicating the system (P for Powertrain, B for Body, C for Chassis, U for Network) followed by four digits that identify the specific fault.
When your check engine light comes on, an OBD-II scanner reads these stored codes to help pinpoint the problem. Generic codes (where the second digit is 0) follow the SAE J2012 standard and mean the same thing on every vehicle. Manufacturer-specific codes (where the second digit is 1) may have different meanings depending on the vehicle brand.
Click any code in the table above to see its full description, possible causes, common symptoms, and step-by-step repair guidance. Use the search box to quickly find a specific code within this category.