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Diagnostic Trouble Code Definitions

DIAGNOSTIC TROUBLE CODE DEFINITIONS

Code No. (1) Circuit Affected
P0031  Front Oxygen Sensor (A/F) Heater Circuit Low Input
P0032  Front Oxygen Sensor (A/F) Heater Circuit High Input
P0037 (2) Rear Heated Oxygen Sensor (HO2S) Heater Circuit Malfunction
P0037 (3) Rear Heated Oxygen Sensor (HO2S) Heater Circuit Low Input
P0038  Rear Heated Oxygen Sensor (HO2S) Heater Circuit High Input
P0065  Air Assist Injector Solenoid Valve Malfunction
P0066  Air Assist Injector Solenoid Valve Circuit Low Input
P0067  Air Assist Injector Solenoid Valve Circuit High Input
P0106  Pressure Sensor Circuit Range/Performance Problem (Low Input)
P0107  Pressure Sensor Circuit Low Input
P0108  Pressure Sensor Circuit High Input
P0111  Intake Air Temperature (IAT) Sensor Circuit Range/Performance Problem
P0112  Intake Air Temperature (IAT) Sensor Circuit Low Input
P0113  Intake Air Temperature (IAT) Sensor Circuit High Input
P0117  Engine Coolant Temperature (ECT) Sensor Circuit Low Input
P0118  Engine Coolant Temperature (ECT) Sensor Circuit High Input
P0121  Throttle Position (TP) Sensor Circuit Range/Performance Problem (High Input)
P0122  Throttle Position (TP) Sensor Circuit Low Input
P0123  Throttle Position (TP) Sensor Circuit High Input
P0125  Insufficient Coolant Temperature For Closed Loop Fuel Control
P0128  Thermostat Malfunction
P0130  Front Oxygen Sensor (A/F) Circuit Range/Performance Problem (Lean)
P0131  Front Oxygen Sensor (A/F) Circuit Malfunction (Open Circuit)
P0132  Front Oxygen Sensor (A/F) Circuit Malfunction (Short Circuit)
P0133  Front Oxygen Sensor (A/F) Circuit Slow Response
P0136 (2) Rear Heated Oxygen Sensor (HO2S) Circuit Malfunction
P0137 (3) Rear Heated Oxygen Sensor (HO2S) Circuit Low Input
P0138 (3) Rear Heated Oxygen Sensor (HO2S) Circuit High Input
P0139  Rear Heated Oxygen Sensor (HO2S) Circuit Slow Response
P0171  Fuel Trim Malfunction (A/F Too Lean)
P0172  Fuel Trim Malfunction (A/F Too Rich)
P0181  Fuel Temperature Sensor "A" Circuit Range/Performance Problem
P0182  Fuel Temperature Sensor "A" Circuit Low Input
P0183 (2) Fuel Temperature Sensor "A" Circuit High Input
P0183 (3) Fuel Temperature Sensor "A" Circuit High Input
P0301  Cylinder No. 1 Misfire Detected
P0302  Cylinder No. 2 Misfire Detected
P0303  Cylinder No. 3 Misfire Detected
P0304  Cylinder No. 4 Misfire Detected
P0327  Knock Sensor (KS) Circuit Low Input
P0328  Knock Sensor (KS) Circuit High Input
P0335  Crankshaft Position (CKP) Sensor Circuit Malfunction
P0336  Crankshaft Position (CKP) Sensor Circuit Range/Performance Problem
P0340  Camshaft Position (CMP) Sensor Circuit Malfunction
P0341  Camshaft Position (CMP) Sensor Circuit Range/Performance Problem
P0420 (4) Catalyst System Efficiency Below Threshold
P0420 (5) Catalyst System Efficiency Below Threshold
P0442  EVAP System Malfunction
P0444 (2) EVAP System Purge Control Valve Circuit Low Input
P0445 (2) EVAP System Purge Control Valve Circuit High Input
P0447  EVAP System Vent Control Circuit Low Input
P0448  EVAP System Vent Control Circuit High Input
P0451  EVAP System Pressure Sensor Range/Performance Problem
P0452 (2) EVAP System Pressure Sensor Low Input
P0452 (3) EVAP System Pressure Sensor Low Input
P0453 (2) EVAP System Pressure Sensor High Input
P0453 (3) EVAP System Pressure Sensor High Input
P0456  EVAP System Malfunction
P0457 (3) EVAP System Malfunction
P0458 (3) EVAP System Purge Control Valve Circuit Low Input
P0459 (3) EVAP System Purge Control Solenoid Valve Circuit High Input
P0461 (2) Fuel Level Sensor Circuit Range/Performance Problem
P0462 (2) Fuel Level Sensor Circuit Low Input
P0462 (3) Fuel Level Sensor Circuit Low Input
P0463 (2) Fuel Level Sensor Circuit High Input
P0463 (3) Fuel Level Sensor Circuit High Input
P0464 (2) Fuel Level Sensor Circuit Intermittent Input
P0464 (3) Fuel Level Sensor Circuit Intermittent Input
P0480 (2) Cooling Fan Relay No. 1 Circuit Low Input
P0483  Cooling Fan Function Problem
P0500 (2) Vehicle Speed Sensor (VSS) Malfunction
P0500 (3) Vehicle Speed Sensor (VSS) Malfunction
P0506  Idle Control System RPM Lower Than Expected
P0507  Idle Control System RPM Higher Than Expected
P0512  Starter Switch Circuit High Input
P0604  Internal Control Module Memory Check Sum Error
P0691 (3) Cooling Fan Relay No. 1 Circuit Low Input
P0692 (3) Cooling Fan Relay No. 1 Circuit High Input
P0703  Brake Switch Input Malfunction (A/T)
P0705 (6) Transmission Range Sensor Circuit Malfunction (A/T)
P0710 (6) Transmission Fluid Temperature Sensor Circuit Malfunction (A/T)
P0715 (6) Torque Converter Turbine Speed Sensor Circuit Malfunction (A/T)
P0720 (6)(7) Output Speed Sensor (Front VSS) Circuit Malfunction (A/T)
P0720 (6)(8) Output Speed Sensor (VSS No. 2) Circuit Malfunction (A/T)
P0725 (6) Engine Speed Input Circuit Malfunction (A/T)
P0731  Gear 1 Incorrect Ratio (A/T)
P0732  Gear 2 Incorrect Ratio (A/T)
P0733  Gear 3 Incorrect Ratio (A/T)
P0734  Gear 4 Incorrect Ratio (A/T)
P0741  Torque Converter Clutch System Malfunction (A/T)
P0743 (6) Torque Converter Clutch System (Lock-Up Duty Solenoid) Electrical (A/T)
P0748 (6) Pressure Control Solenoid (Line Pressure Duty Solenoid) Electrical (A/T)
P0753 (6) Shift Solenoid "A" (No. 1) Electrical (A/T)
P0758 (6) Shift Solenoid "B" (No. 2) Electrical (A/T)
P0778 (6) 2-4 Brake Pressure Control Solenoid Valve Circuit Malfunction (A/T)
P0785 (6) 2-4 Brake Timing Control Solenoid Valve Circuit Malfunction (A/T)
P0851 (3) Inhibitor Switch Circuit Low Input (A/T)
P0851 (3) Neutral Position Switch Circuit Low Input (M/T)
P0852 (3) Inhibitor Switch Circuit High Input (A/T)
P0852 (3) Neutral Position Switch Circuit High Input (M/T)
P0864 (3) A/T Diagnosis Input Signal Circuit Malfunction
P0865 (3) A/T Diagnosis Input Signal Circuit Low Input
P0866 (3) A/T Diagnosis Input Signal Circuit High Input
P1110 (2) Atmospheric Pressure Sensor Circuit Low Input
P1110 (3) Atmospheric Pressure Sensor Circuit Low Input
P1111 (2) Atmospheric Pressure Sensor Circuit High Input
P1111 (3) Atmospheric Pressure Sensor Circuit High Input
P1112 (2) Atmospheric Pressure Sensor Circuit Range/Performance Problem
P1112 (3) Atmospheric Pressure Sensor Circuit Range/Performance Problem
P1137  Front Oxygen Sensor (A/F) Circuit Range/Performance Problem
P1142  Throttle Position (TP) Sensor Circuit Range/Performance Problem (Low Input)
P1146  Pressure Sensor Circuit Range/Performance Problem (High Input)
P1400  Fuel Tank Pressure Control Solenoid Valve Circuit Low Input
P1420  Fuel Tank Pressure Control Solenoid Valve Circuit High Input
P1442  Fuel Level Sensor Circuit Range/Performance Problem 2
P1443  EVAP System Vent Control Function Problem
P1446 (3) EVAP System Atmospheric Pressure Solenoid Valve Circuit Low Input
P1447 (3) EVAP System Atmospheric Pressure Solenoid Valve Circuit High Input
P1448 (3) EVAP System Atmospheric Pressure Solenoid Valve Circuit Range/Performance Problem
P1480 (2) Cooling Fan Relay No. 1 Circuit High Input
P1507  Idle Control System Malfunction (Fail-Safe)
P1510  Idle Air Control (IAC) Solenoid Valve Signal No. 1 Circuit Low Input
P1511  Idle Air Control (IAC) Solenoid Valve Signal No. 1 Circuit High Input
P1512  Idle Air Control (IAC) Solenoid Valve Signal No. 2 Circuit Low Input
P1513  Idle Air Control (IAC) Solenoid Valve Signal No. 2 Circuit High Input
P1514  Idle Air Control (IAC) Solenoid Valve Signal No. 3 Circuit Low Input
P1515  Idle Air Control (IAC) Solenoid Valve Signal No. 3 Circuit High Input
P1516  Idle Air Control (IAC) Solenoid Valve Signal No. 4 Circuit Low Input
P1517  Idle Air Control (IAC) Solenoid Valve Signal No. 4 Circuit High Input
P1518  Starter Switch Circuit Low Input
P1540  Vehicle Speed Sensor (VSS) Malfunction 2
P1560  Back-Up Voltage Circuit Malfunction
P1590 (2) Inhibitor Switch Circuit High Input (A/T)
P1591 (2) Inhibitor Switch Circuit Low Input (A/T)
P1592 (2) Neutral Position Switch Circuit Malfunction (M/T)
P1594 (2) A/T Diagnosis Input Signal Circuit Malfunction
P1595 (2) A/T Diagnosis Input Signal Circuit Low Input
P1596 (2) A/T Diagnosis Input Signal Circuit High Input
P1698  Engine Torque Control Cut Signal Circuit Low Input (A/T)
P1699  Engine Torque Control Cut Signal Circuit High Input (A/T)
P1700 (6) Throttle Position (TP) Sensor Circuit Malfunction (A/T)
P1701  Cruise Control Set Signal Circuit Malfunction (A/T)
P1703 (6) Low Clutch Timing Control Solenoid Valve Circuit Malfunction (A/T)
P1711  Engine Torque Control Signal No. 1 Circuit Malfunction (A/T)
P1712  Engine Torque Control Signal No. 2 Circuit Malfunction (A/T)
(1) DTC applies to all models unless otherwise specified.
(2) Forester, Impreza and Outback Sport.
(3) Legacy and Outback.
(4) Forester.
(5) Impreza, Outback Sport, Legacy and Outback.
(6) Covered in entirety in appropriate DIAGNOSTICS article in AUTOMATIC TRANSMISSIONS in TRANSAXLE/TRANSMISSION.
(7) Impreza and Outback Sport.
(8) Forester, Legacy and Outback.