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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

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All severities9253 Low priority305 Check soon8256 Urgent621

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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 1–24 of 305

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P0051Heated Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 1Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0051 means Heated Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 1. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0057Heated Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 2Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0057 means Heated Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 2. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0420Catalyst System Efficiency Below ThresholdLow priorityEmissions System60–150 minutesDiagnose P0420 catalyst efficiency below threshold on Bank 1. Learn what O2 sensor data can show and what to check before replacing the catalytic converter.P0442EVAP System Small Leak DetectedLow priorityEmissions System30–120 minutesFix P0442 evaporative emission system leak. Learn common causes of small EVAP leaks and how to find them.B012FA/V Sensor Washer Fluid A Control CircuitLow priorityBody & Restraints45–120 minutes for initial diagnosisB012F concerns a/v sensor washer fluid a control circuit. Learn what this fault indicates and where to begin diagnosis.B0130A/V Sensor Washer Fluid B Control CircuitLow priorityBody & Restraints45–120 minutes for initial diagnosisB0130 concerns a/v sensor washer fluid b control circuit. Learn what this fault indicates and where to begin diagnosis.B0131A/V Sensor Washer Fluid C Control CircuitLow priorityBody & Restraints45–120 minutes for initial diagnosisB0131 concerns a/v sensor washer fluid c control circuit. Learn what this fault indicates and where to begin diagnosis.B0132A/V Sensor Washer Fluid D Control CircuitLow priorityBody & Restraints45–120 minutes for initial diagnosisB0132 concerns a/v sensor washer fluid d control circuit. Learn what this fault indicates and where to begin diagnosis.B0133A/V Sensor Washer Fluid E Control CircuitLow priorityBody & Restraints45–120 minutes for initial diagnosisB0133 concerns a/v sensor washer fluid e control circuit. Learn what this fault indicates and where to begin diagnosis.B0134A/V Sensor Washer Fluid F Control CircuitLow priorityBody & Restraints45–120 minutes for initial diagnosisB0134 concerns a/v sensor washer fluid f control circuit. Learn what this fault indicates and where to begin diagnosis.C0083Tire Pressure Monitor Malfunction IndicatorLow priorityChassis & Brakes45–120 minutes for initial diagnosisC0083 means Tire Pressure Monitor Malfunction Indicator. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.P0030HO2S Heater Control Circuit Bank 1 Sensor 1Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0030 relates to ho2s heater control circuit bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0031HO2S Heater Control Circuit Low Bank 1 Sensor 1Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0031 relates to ho2s heater control circuit low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0032HO2S Heater Control Circuit High Bank 1 Sensor 1Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0032 relates to ho2s heater control circuit high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0036HO2S Heater Control Circuit Bank 1 Sensor 2Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0036 relates to ho2s heater control circuit bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0037HO2S Heater Control Circuit Low Bank 1 Sensor 2Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0037 relates to ho2s heater control circuit low bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0038HO2S Heater Control Circuit High Bank 1 Sensor 2Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0038 relates to ho2s heater control circuit high bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P0042HO2S Heater Control Circuit Bank 1 Sensor 3Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0042 relates to ho2s heater control circuit bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P0043HO2S Heater Control Circuit Low Bank 1 Sensor 3Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0043 relates to ho2s heater control circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P0044HO2S Heater Control Circuit High Bank 1 Sensor 3Low prioritySensors & Electronics30–120 minutes for initial diagnosisP0044 relates to ho2s heater control circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P0050Heated Oxygen Sensor Heater Control Circuit Bank 2 Sensor 1Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0050 means Heated Oxygen Sensor Heater Control Circuit Bank 2 Sensor 1. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0056Heated Oxygen Sensor Heater Control Circuit Bank 2 Sensor 2Low prioritySensors & Electronics45–120 minutes for initial diagnosisP0056 means Heated Oxygen Sensor Heater Control Circuit Bank 2 Sensor 2. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P0071Ambient Air Temperature Sensor Range/PerformanceLow prioritySensors & Electronics45–120 minutes for initial diagnosisP0071 means Ambient Air Temperature Sensor Range/Performance. Learn the likely symptoms, causes, safety implications, and a practical diagnostic order.P009AIntake Air Temperature/Ambient Air Temperature CorrelationLow prioritySensors & Electronics30–120 minutes for initial diagnosisP009A relates to intake air temperature/ambient air temperature correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.