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Engine Performance DTCS

NOTE: Retrieval of some diagnostic codes may require the use of special OEM tester or flash method using instrument cluster indicator. For procedures/testing of codes not shown below, refer to appropriate system article.
ENGINE PERFORMANCE DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTC Description
P0101 MAF Sensor Circuit Range/Performance Problem
P0102 MAF Sensor Circuit Low Input
P0103 MAF Sensor Circuit High Input
P0106 Pressure Sensor Range/Performance
P0107 Pressure Sensor Circuit Low Input
P0108 Pressure Sensor Circuit High Input
P0116 ECT Sensor Circuit Low Input (Legacy models only)
P0117 ECT Sensor Circuit Low Input (Forester and Impreza models only)
P0117 ECT Sensor Circuit High Input (Legacy models only)
P0118 ECT Sensor Circuit High Input (Forester and Impreza models only)
P0121 Throttle Position (TP) Sensor Range/Performance (High Input)
P0122 Throttle Position (TP) Sensor Ckt (Low Input)
P0123 Throttle Position (TP) Sensor Ckt (High Input)
P0125 Engine Coolant Temp. Too Low For Closed Loop Control
P0130 Front O2S Circuit Malfunction
P0133 Front O2S Circuit Slow Response
P0135 Front O2S Heater Circuit Malfunction
P0136 Rear O2S Circuit Malfunction
P0139 Rear O2S Circuit Slow Response
P0141 Rear O2S Heater Circuit Malfunction
P0170 Fuel Trim Malfunction
P0181 Fuel Temp. Sensor "A" Circuit Range/Performance
P0182 Fuel Temp. Sensor "A" Circuit Low Input
P0183 Fuel Temp. Sensor "A" Circuit High Input
P0261 Fuel Injector Circuit Low Input No. 1
P0262 Fuel Injector Circuit High Input No. 1
P0264 Fuel Injector Circuit Low Input No. 2
P0265 Fuel Injector Circuit High Input No. 2
P0267 Fuel Injector Circuit Low Input No. 3
P0268 Fuel Injector Circuit High Input No. 3
P0270 Fuel Injector Circuit Low Input No. 4
P0271 Fuel Injector Circuit High Input No. 4
P0301 Cylinder No. 1 Misfire Detected
P0302 Cylinder No. 2 Misfire Detected
P0303 Cylinder No. 3 Misfire Detected
P0304 Cylinder No. 4 Misfire Detected
P0325 Knock Sensor (KS) Circuit Malfunction
P0335 Crankshaft Position (CKP) Sensor Malfunction
P0336 Crankshaft Position Sensor Range/Performance Problem
P0340 Camshaft Position (CMP) Sensor Circuit Malfunction
P0341 Camshaft Position Sensor Range/Performance Problem
P0400 EGR Flow Malfunction
P0403 EGR Circuit Low Input
P0420 CAT Efficiency Below Threshold
P0440 EVAP Emission Control System
P0441 Incorrect EVAP Purge Flow
P0443 EVAP Purge Circuit Low Input
P0446 EVAP Emission Control System Vent Control Low Input
P0451 EVAP Pressure Sensor Range/Performance Problem
P0452 EVAP Pressure Sensor Low Input (Forester & 2.5L Impreza only)
P0452 EVAP Pressure Sensor Low Input (Legacy & 2.2L Impreza only)
P0453 EVAP Pressure Sensor High Input (All except Legacy)
P0453 EVAP Pressure Sensor High Input (Legacy models only)
P0461 Fuel Level Sensor Ckt Range/Performance Problem
P0462 Fuel Level Sensor Circuit Low Input
P0463 Fuel Level Sensor Circuit High Input
P0480 Cooling Fan Relay No. 1 Low Input
P0483 Cooling Fan Function Problem
P0500 Vehicle Speed Sensor (VSS) Malfunction (Forester and Impreza models only)
P0500 Vehicle Speed Sensor (VSS) Malfunction (Legacy models only)
P0505 Idle Control System Malfunction
P0506 Idle RPM Too Low
P0507 Idle RPM Too High
P0600 Serial Communication Link Malfunction
P0601 Internal Control Module Memory Check Sum Error
P1100 Starter Switch Circuit Low Input
P1101 Neutral Position Switch High Input (A/T)
P1101 Neutral Position Switch Ckt Malfunction (M/T)
P1102 Pressure Sources Switching Solenoid Valve Ckt Low Input
P1103 Engine Torque Control Signal Ckt Malfunction
P1120 Starter Switch Circuit High Input
P1121 Neutral Position Switch Low Input (A/T)
P1122 Pressure Sources Switching Solenoid Valve Circuit High Input
P1141 MAF Sensor Ckt Range/Performance Problem (High Input)
P1142 Throttle Position Sensor Ckt Range/Performance (Low Input)
P1143 Pressure Sensor Ckt Range/Performance Problem (Low Input)
P1144 Pressure Sensor Ckt Range/Performance Problem (High Input)
P1400 Fuel Tank Pressure Control Solenoid Ckt Low Input
P1420 Fuel Tank Pressure Control Solenoid Valve Ckt High Input
P1421 EGR Circuit High Input
P1422 EVAP Purge Control Valve Ckt High Input
P1423 EVAP Vent Control High Input
P1440 Fuel Tank Pressure Control System Function Problem (Low Input)
P1441 Fuel Tank Pressure Control System Function (High Input)
P1442 Fuel Level Sensor Ckt Range/Performance Problem 2
P1443 EVAP Vent Control Function Problem (Impreza 2.2L models and all Legacy models)
P1507 Idle Control System Malfunction (Fail-Safe)
P1520 Radiator Fan Relay 1 Circuit High Input
P1540 Vehicle Speed Sensor Malfunction 2