Engine Controls - Self-Diagnostics - 2.2L & 2.5L

• Introduction
• Self-Diagnostic System
  • On-Board Diagnostics
  • Two-Trip Detection Logic
  • Freeze-Frame Data
  • Malfunction Indicator Light (Mil) Inspection
    • Notes
    • Operation
    • Hard Failures
    • Intermittent Failures
  • Diagnostic Procedure
  • Basic Diagnostic Procedure
  • Clearing Diagnostic Trouble Codes
  • Verification Procedure
    • Notes
    • Subaru Select Monitor (SSM) Procedure
    • OBD-II Generic Scan Tool Procedure
  • ECM Location
• Programming
  • ISC Initialization
• Summary
• Diagnostic Trouble Code Definitions
• Diagnostic Tests
  • Notes
  • DTC P0031: Front Heated Oxygen Sensor (Ho2S) Heater Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P0032: Front Ho2S Heater Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0037: Rear Ho2S Heater Circuit Malfunction - Legacy & Outback 2.5L A/T
  • DTC P0038: Rear Ho2S Heater Circuit High Output - Legacy & Outback 2.5L A/T
  • DTC P0065: Air Assist Injector Solenoid Valve Circuit Malfunction - Legacy & Outback 2.5L A/T
  • DTC P0066: Air Assist Injector Solenoid Valve Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P0067: Air Assist Injector Solenoid Valve Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0106: Intake Air Temperature & Pressure Sensor Circuit Range/Performance Problem - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0106: Intake Manifold Pressure Sensor Circuit Range/Performance Problem - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0107: Intake Air Temperature & Pressure Sensor Circuit Low Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0107: Intake Manifold Pressure Sensor Circuit Low Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0108: Intake Air Temperature & Pressure Sensor Circuit High Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0108: Intake Manifold Pressure Sensor Circuit High Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0111: Intake Air Temperature (IAT) Sensor Circuit Range/Performance Problem - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0111: Intake Air Temperature (IAT) Sensor Circuit Range/Performance Problem - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0112: Intake Air Temperature (IAT) Sensor Circuit Low Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0112: Intake Air Temperature (IAT) Sensor Circuit Low Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0113: Intake Air Temperature (IAT) Sensor Circuit High Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0113: Intake Air Temperature (IAT) Sensor Circuit High Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0116: Engine Coolant Temperature (ECT) Sensor Circuit Low Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0117: Engine Coolant Temperature (ECT) Sensor Circuit High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0117: Engine Coolant Temperature (ECT) Sensor Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P0118: Engine Coolant Temperature (ECT) Sensor Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0121: Throttle Position (TP) Sensor Circuit Range/Performance Problem (High Input) - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0121: Throttle Position (TP) Sensor Circuit Range/Performance Problem (High Input) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0122: Throttle Position (TP) Sensor Circuit Low Input
  • DTC P0123: Throttle Position (TP) Sensor Circuit High Input
  • DTC P0125: Engine Coolant Temperature Too Low For Closed Loop Fuel Control
  • DTC P0128: Thermostat Malfunction - Legacy & Outback 2.5L A/T
  • DTC P0130: Front Ho2S Circuit Range/Performance Problem - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0131: Front Ho2S Circuit Range/Performance Problem (Low Input) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0131: Front Ho2S Circuit Malfunction (Open Circuit) - Legacy & Outback 2.5L A/T
  • DTC P0132: Front Ho2S Circuit Range/Performance Problem (High Input) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0132: Front Ho2S Circuit Malfunction (Short Circuit) - Legacy & Outback 2.5L A/T
  • DTC P0133: Front Ho2S Circuit Slow Response
  • DTC P0136: Rear Ho2S Circuit Malfunction
  • DTC P0139: Rear Ho2S Circuit Slow Response
  • DTC P0141: Rear Ho2S Heater Circuit Malfunction/Low Input - Forester & IMPREZA 2.5L
  • DTC P0141: Rear Ho2S Heater Circuit Malfunction/Low Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0170: Fuel Trim Malfunction - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0171: Fuel Trim Malfunction (Too Lean) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0172: Fuel Trim Malfunction (Too Rich) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0181: Fuel Temperature Sensor "A" Circuit Range/Performance Problem
  • DTC P0182: Fuel Temperature Sensor "A" Circuit Low Input
  • DTC P0183: Fuel Temperature Sensor "A" Circuit High Input
  • DTC P0301, P0302, P0303 & P0304: Cylinders No. 1-4 Misfire Detected
  • DTC P0325: Knock Sensor (KS) Circuit High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0327: Knock Sensor (KS) Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P0328: Knock Sensor (KS) Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0335: Crankshaft Position (CKP) Sensor Circuit Malfunction
  • DTC P0336: Crankshaft Position (CKP) Sensor Circuit Range/Performance Problem
  • DTC P0340: Camshaft Position (CMP) Sensor Circuit Malfunction
  • DTC P0341: Camshaft Position (CMP) Sensor Circuit Range/Performance Problem
  • DTC P0420: Catalyst System Efficiency Below Threshold
  • DTC P0440: EVAP System Malfunction - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0442: EVAP System Purge Control Valve Circuit Malfunction - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0443: EVAP System Purge Control Valve Circuit Low Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0444: EVAP System Purge Control Valve Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P0445: EVAP System Purge Control Valve Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0446: EVAP System Vent Control Circuit Low Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0447: EVAP System Vent Control Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P0448: EVAP System Vent Control Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0451: EVAP System Pressure Sensor Range/Performance Problem
  • DTC P0452: EVAP System Pressure Sensor Low Input - Forester, IMPREZA & Outback Sport
  • DTC P0452: EVAP System Pressure Sensor Low Input - Legacy & Outback 2.5L
  • DTC P0453: EVAP System Pressure Sensor High Input - Forester, IMPREZA & Outback Sport
  • DTC P0453: EVAP System Pressure Sensor High Input - Legacy & Outback 2.5L
  • DTC P0456: EVAP System Malfunction - Legacy & Outback 2.5L A/T
  • DTC P0461: Fuel Level Sensor Circuit Range/Performance Problem
  • DTC P0462: Fuel Level Sensor Circuit Low Input
  • DTC P0463: Fuel Level Sensor Circuit High Input
  • DTC P0464: Fuel Level Sensor Intermittent Input - Legacy & Outback 2.5L A/T
  • DTC P0480: Cooling Fan Relay No. 1 Circuit Low Input
  • DTC P0483: Cooling Fan Function Problem
  • DTC P0500: Vehicle Speed Sensor (VSS) Malfunction
  • DTC P0505: Idle Control System Low Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0506: Idle Control System Rpm Lower Than Expected - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P0506: Idle Control System Rpm Lower Than Expected - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0507: Idle Control System Rpm Higher Than Expected
  • DTC P0512: Starter Switch Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P0601: Internal Control Module Memory Check Sum Error - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P0604: Internal Control Module Memory Check Sum Error - Legacy & Outback 2.5L A/T
  • DTC P0703: Brake Switch Input Malfunction (A/T)
  • DTC P0731, DTC P0732, DTC P0733 & DTC P0734
  • DTC P0741: Torque Converter Clutch System Malfunction (A/T)
  • DTC P1100: Starter Switch Circuit Low Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1101: Neutral Position Switch Circuit High Input (A/T) - Forester, IMPREZA & Outback Sport
  • DTC P1101: Neutral Position Switch Circuit Low Input (M/T) - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1103: Engine Torque Control Signal No. 1 Circuit Malfunction (A/T) - Forester, IMPREZA & Outback Sport
  • DTC P1106: Engine Torque Control Signal No. 2 Circuit Malfunction (A/T) - Forester, IMPREZA & Outback Sport
  • DTC P1110: Atmospheric Pressure Sensor Circuit Low Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1110: Atmospheric Pressure Sensor Circuit Low Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1111: Atmospheric Pressure Sensor Circuit High Input- Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1111: Atmospheric Pressure Sensor Circuit High Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1112: Atmospheric Pressure Sensor Circuit Range/Performance Problem - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1112: Atmospheric Pressure Sensor Circuit Range/Performance Problem - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1115: Engine Torque Control Cut Signal Circuit High Input - Forester, IMPREZA & Outback Sport
  • DTC P1116: Engine Torque Control Cut Signal Circuit Low Input - Forester, IMPREZA & Outback Sport
  • DTC P1120: Starter Switch Circuit High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1121: Neutral Position Switch Circuit Low Input (A/T) - Forester, IMPREZA & Outback Sport
  • DTC P1121: Neutral Position Switch Circuit High Input (M/T) - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1130: Front Ho2S Circuit Malfunction (Open Circuit) - Forester & IMPREZA 2.5L
  • DTC P1130: Front Ho2S Circuit Malfunction (Open Circuit) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1131: Front Ho2S Circuit Malfunction (Short Circuit) - Forester & IMPREZA 2.5L
  • DTC P1131: Front Ho2S Circuit Malfunction (Short Circuit) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1132: Front Ho2S Heater Circuit Low Input - Forester & IMPREZA 2.5L
  • DTC P1132: Front Ho2S Heater Circuit Low Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1133: Front Ho2S Heater Circuit High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1134: Front Ho2S Micro-Computer Problem - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1137: Front Ho2S Circuit Range/Performance Problem - Legacy & Outback 2.5L A/T
  • DTC P1139: Front Ho2S No. 1 Heater Circuit Range/Performance Problem - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1142: Throttle Position (TP) Sensor Circuit Range/Performance Problem (Low Input) - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1142: Throttle Position (TP) Sensor Circuit Range/Performance Problem (Low Input) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1146: Pressure Sensor Circuit Range/Performance Problem (High Input) - Legacy & Outback 2.5L A/T
  • DTC P1151: Rear Ho2S Heater Circuit High Input - Forester & IMPREZA 2.5L
  • DTC P1151: Rear Ho2S Heater Circuit High Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1207: Air Assist Injector Solenoid Valve Circuit Low Input - Forester & IMPREZA 2.5L
  • DTC P1208: Air Assist Injector Solenoid Valve Circuit High Input - Forester & IMPREZA 2.5L
  • DTC P1325: Knock Sensor (KS) Circuit Low Input - Forester & IMPREZA 2.5L
  • DTC P1400: Fuel Tank Pressure Control Solenoid Valve Circuit Low Input
  • DTC P1420: Fuel Tank Pressure Control Solenoid Valve Circuit High Input
  • DTC P1422: EVAP System Purge Control Solenoid Valve Circuit High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1423: EVAP System Vent Control High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1442: Fuel Level Sensor Circuit Range/Performance Problem 2 - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1443: EVAP System Vent Control Function Problem
  • DTC P1445: Air Assist Injector Solenoid Valve Malfunction - Forester & IMPREZA 2.5L
  • DTC P1480: Cooling Fan Relay No. 1 Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P1490: Thermostat Malfunction - Forester & IMPREZA 2.5L
  • DTC P1505: Idle Control System Circuit High Input - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1507: Idle Control System Malfunction (Fail-Safe) - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1507: Idle Control System Malfunction (Fail-Safe) - IMPREZA 2.2L, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1510, P1512, P1514 & P1516: Idle Air Control (IAC) Solenoid Valve Signal No. 1-4 Circuits Low Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1511, P1513, P1515 & P1517: Idle Air Control (IAC) Solenoid Valve Signal No. 1-4 Circuits High Input - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1518: Starter Switch Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P1520: Radiator Fan Relay No. 1 Circuit High Input - Forester, IMPREZA, Legacy & Outback 2.5L M/T & Outback Sport
  • DTC P1540: Vehicle Speed Sensor (VSS) Malfunction 2 - Forester, IMPREZA 2.5L & Legacy & Outback 2.5L A/T
  • DTC P1560: Back-Up Voltage Circuit Malfunction
  • DTC P1590: Neutral Position Switch Circuit High Input - Legacy & Outback 2.5L A/T
  • DTC P1591: Neutral Position Switch Circuit Low Input - Legacy & Outback 2.5L A/T
  • DTC P1701: Cruise Control Set Signal Circuit Malfunction (A/T)