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9,253 diagnostic guides

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Find codes by symptomChoose what you notice to search matching code guides.

Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 1057–1080 of 9253

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P01ECEngine Coolant Heater B Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP01EC relates to engine coolant heater b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EDEngine Coolant Heater B Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP01ED relates to engine coolant heater b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EEEngine Coolant Heater B Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01EE relates to engine coolant heater b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EFEngine Coolant Heater B Control Circuit PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP01EF relates to engine coolant heater b control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F0Coolant Temperature Relapsed Below Diagnostic Monitoring TemperatureCheck soonEngine Problems30–120 minutes for initial diagnosisP01F0 relates to coolant temperature relapsed below diagnostic monitoring temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F1O2 Sensor Circuit Bank 1 Sensor 4Check soonSensors & Electronics30–120 minutes for initial diagnosisP01F1 relates to o2 sensor circuit bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F2O2 Sensor Circuit Low Voltage Bank 1 Sensor 4Check soonElectrical & Charging System30–120 minutes for initial diagnosisP01F2 relates to o2 sensor circuit low voltage bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F3O2 Sensor Circuit High Voltage Bank 1 Sensor 4Check soonElectrical & Charging System30–120 minutes for initial diagnosisP01F3 relates to o2 sensor circuit high voltage bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F4O2 Sensor Circuit Slow Response Bank 1 Sensor 4Check soonSensors & Electronics30–120 minutes for initial diagnosisP01F4 relates to o2 sensor circuit slow response bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F5O2 Sensor Circuit No Activity Detected Bank 1 Sensor 4Check soonSensors & Electronics30–120 minutes for initial diagnosisP01F5 relates to o2 sensor circuit no activity detected bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F6O2 Sensor Signal Biased/Stuck Lean Bank 1 Sensor 4Check soonSensors & Electronics30–120 minutes for initial diagnosisP01F6 relates to o2 sensor signal biased/stuck lean bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F7O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 4Check soonSensors & Electronics30–120 minutes for initial diagnosisP01F7 relates to o2 sensor signal biased/stuck rich bank 1 sensor 4. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F8Engine Coolant Heater A Control Circuit Driver Current/Temperature Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01F8 relates to engine coolant heater a control circuit driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F9Engine Coolant Heater B Control Circuit Driver Current/Temperature Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01F9 relates to engine coolant heater b control circuit driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01FATurbocharger Outlet Pressure Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP01FA relates to turbocharger outlet pressure sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P01FBTurbocharger Outlet Pressure Sensor B Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP01FB relates to turbocharger outlet pressure sensor b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P01FCTurbocharger Outlet Pressure Sensor B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP01FC relates to turbocharger outlet pressure sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P01FDTurbocharger Outlet Pressure Sensor B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP01FD relates to turbocharger outlet pressure sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01FETurbocharger Outlet Pressure Sensor B Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP01FE relates to turbocharger outlet pressure sensor b intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P01FFTurbocharger Outlet Pressure Sensor A/B CorrelationCheck soonSensors & Electronics30–120 minutes for initial diagnosisP01FF relates to turbocharger outlet pressure sensor a/b correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P0200Injector Circuit/OpenCheck soonFuel System45–120 minutes for initial diagnosisP0200 means Injector Circuit/Open. Learn the likely symptoms, common causes, and a safe diagnostic order before replacing parts.P0201Injector Circuit Malfunction Cylinder 1Fuel SystemDiagnose P0201 fuel injector circuit fault on cylinder 1 - wiring, driver, and injector causes plus fixes.P0207Injector Circuit/Open Cylinder 7Check soonFuel System45–120 minutes for initial diagnosisP0207 means Injector Circuit/Open Cylinder 7. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P020ACylinder 1 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP020A relates to cylinder 1 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.