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OBD2 · FAULT CODE

OBD2 fault codes,
explained one by one.

Clear explanations of the most common OBD2 fault codes: what each code means, the symptoms it causes, the most likely culprits, and what to check first.

P0001
Fuel Volume Regulator Control Circuit/Open
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P0002
Fuel Volume Regulator Control Circuit Range/Performance
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P0003
Fuel Volume Regulator Control Circuit Low
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P0004
Fuel Volume Regulator Control Circuit High
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P0005
Fuel Shutoff Valve A Control Circuit/Open
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P0006
Fuel Shutoff Valve A Control Circuit Low
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P0007
Fuel Shutoff Valve A Control Circuit High
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P0011
Camshaft Position Timing Over-Advanced (Bank 1)
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P0016
Crankshaft–Camshaft Position Correlation (Bank 1 Sensor A)
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P0100
Mass or Volume Air Flow Circuit
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P0101
Mass Air Flow Circuit Range/Performance
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P0102
Mass Air Flow (MAF) Circuit Low Input
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P0103
Mass Air Flow Circuit High Input
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P0104
Mass Air Flow Circuit Intermittent
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P0105
Manifold Absolute Pressure/Barometric Pressure Circuit
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P0106
MAP/BARO Circuit Range/Performance
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P0107
MAP/BARO Circuit Low Input
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P0108
MAP/BARO Circuit High Input
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P0109
MAP/BARO Circuit Intermittent
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P0110
Intake Air Temperature Sensor 1 Circuit
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P0111
Intake Air Temperature Sensor 1 Range/Performance
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P0112
Intake Air Temperature Sensor 1 Circuit Low
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P0113
Intake Air Temperature Sensor 1 Circuit High
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P0114
Intake Air Temperature Sensor 1 Circuit Intermittent
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P0115
Engine Coolant Temperature Sensor Circuit
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P0116
Engine Coolant Temperature Sensor Range/Performance
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P0117
Engine Coolant Temperature Sensor Circuit Low
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P0118
Engine Coolant Temperature Sensor Circuit High
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P0119
Engine Coolant Temperature Sensor Circuit Intermittent
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P0120
Throttle/Pedal Position Sensor A Circuit
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P0121
Throttle/Pedal Position Sensor A Range/Performance
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P0122
Throttle/Pedal Position Sensor A Circuit Low
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P0123
Throttle/Pedal Position Sensor A Circuit High
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P0124
Throttle/Pedal Position Sensor A Circuit Intermittent
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P0128
Coolant Temperature Below Thermostat Regulating Temperature
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P0130
O2 Sensor Circuit (Bank 1, Sensor 1)
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P0131
O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1)
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P0132
O2 Sensor Circuit High Voltage (Bank 1, Sensor 1)
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P0133
O2 Sensor Circuit Slow Response (Bank 1, Sensor 1)
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P0134
O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 1)
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P0135
O2 Sensor Heater Circuit (Bank 1, Sensor 1)
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P0136
O2 Sensor Circuit (Bank 1, Sensor 2)
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P0137
O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2)
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P0138
O2 Sensor Circuit High Voltage (Bank 1, Sensor 2)
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P0139
O2 Sensor Circuit Slow Response (Bank 1, Sensor 2)
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P0140
O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 2)
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P0141
O2 Sensor Heater Circuit (Bank 1, Sensor 2)
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P0150
O2 Sensor Circuit (Bank 2, Sensor 1)
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P0151
O2 Sensor Circuit Low Voltage (Bank 2, Sensor 1)
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P0152
O2 Sensor Circuit High Voltage (Bank 2, Sensor 1)
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P0153
O2 Sensor Circuit Slow Response (Bank 2, Sensor 1)
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P0171
System Too Lean (Bank 1)
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P0172
System Too Rich (Bank 1)
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P0174
System Too Lean (Bank 2)
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P0220
Throttle/Pedal Position Sensor B Circuit
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P0221
Throttle/Pedal Position Sensor B Range/Performance
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P0222
Throttle/Pedal Position Sensor B Circuit Low
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P0223
Throttle/Pedal Position Sensor B Circuit High
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P0224
Throttle/Pedal Position Sensor B Circuit Intermittent
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P0300
Random/Multiple Cylinder Misfire Detected
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P0301
Cylinder 1 Misfire Detected
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P0302
Cylinder 2 Misfire Detected
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P0303
Cylinder 3 Misfire Detected
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P0304
Cylinder 4 Misfire Detected
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P0305
Cylinder 5 Misfire Detected
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P0306
Cylinder 6 Misfire Detected
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P0307
Cylinder 7 Misfire Detected
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P0308
Cylinder 8 Misfire Detected
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P0309
Cylinder 9 Misfire Detected
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P0310
Cylinder 10 Misfire Detected
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P0311
Cylinder 11 Misfire Detected
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P0312
Cylinder 12 Misfire Detected
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P0325
Knock Sensor 1 Circuit (Bank 1)
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P0326
Knock Sensor 1 Circuit Range/Performance (Bank 1)
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P0327
Knock Sensor 1 Circuit Low Input (Bank 1)
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P0328
Knock Sensor 1 Circuit High Input (Bank 1)
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P0330
Knock Sensor 2 Circuit (Bank 2)
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P0335
Crankshaft Position Sensor A Circuit
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P0336
Crankshaft Position Sensor A Range/Performance
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P0337
Crankshaft Position Sensor A Circuit Low
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P0338
Crankshaft Position Sensor A Circuit High
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P0340
Camshaft Position Sensor A Circuit (Bank 1 or Single Sensor)
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P0341
Camshaft Position Sensor A Range/Performance (Bank 1 or Single Sensor)
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P0342
Camshaft Position Sensor A Circuit Low (Bank 1 or Single Sensor)
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P0343
Camshaft Position Sensor A Circuit High (Bank 1 or Single Sensor)
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P0350
Ignition Coil Primary/Secondary Circuit
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P0351
Ignition Coil A Primary/Secondary Circuit
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P0352
Ignition Coil B Primary/Secondary Circuit
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P0353
Ignition Coil C Primary/Secondary Circuit
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P0354
Ignition Coil D Primary/Secondary Circuit
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P0400
Exhaust Gas Recirculation Flow Malfunction
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P0401
Exhaust Gas Recirculation (EGR) Flow Insufficient
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P0402
Exhaust Gas Recirculation Flow Excessive
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P0403
Exhaust Gas Recirculation Control Circuit
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P0404
Exhaust Gas Recirculation Circuit Range/Performance
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P0405
Exhaust Gas Recirculation Sensor A Circuit Low
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P0406
Exhaust Gas Recirculation Sensor A Circuit High
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P0410
Secondary Air Injection System
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P0411
Secondary Air Injection System Incorrect Flow
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P0420
Catalyst System Efficiency Below Threshold (Bank 1)
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P0430
Catalyst System Efficiency Below Threshold (Bank 2)
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P0440
EVAP System
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P0441
EVAP System Incorrect Purge Flow
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P0442
EVAP System Leak Detected (Small Leak)
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P0455
EVAP System Leak Detected (Large Leak)
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P0500
Vehicle Speed Sensor 'A' Malfunction
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P0505
Idle Control System
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P0506
Idle Control System RPM Lower Than Expected
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P0507
Idle Control System RPM Higher Than Expected
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P0560
System Voltage
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P0562
System Voltage Low
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P0563
System Voltage High
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P0600
Serial Communication Link
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P0601
Internal Control Module Memory Check Sum Error
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P0606
PCM Processor Fault
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P0700
Transmission Control System Malfunction (MIL Request)
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P0705
Transmission Range Sensor Circuit
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P0715
Input/Turbine Speed Sensor Circuit
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P0720
Output Speed Sensor Circuit
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P0740
Torque Converter Clutch Circuit
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