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Diagnostic Trouble Code (DTC) Identification

DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION

DTC Description Probable Cause
P0100 (1) Mass Airflow (MAF) Sensor Circuit Malfunction Open/Short Circuit, MAF Sensor Or ECM
P0101 (1) Mass Airflow (MAF) Circuit Range/Performance Fault MAF Sensor
P0110  Intake Air Temperature (IAT) Sensor Circuit Open/Short Circuit, IAT Sensor Or ECM
P0115  Engine Coolant Temperature (ECT) Sensor Circuit Fault Open/Short Circuit, ECT Sensor Or ECM
P0116 (1) ECT Sensor Circuit Range/Performance Fault ECT Sensor Or Cooling System
P0120  Throttle Position (TP) Sensor Malfunction Open/Short Circuit, TP Sensor Or ECM
P0121 (1) Throttle Position (TP) Sensor Circuit Range/Performance TP Sensor or ECM
P0125  Insufficient Coolant Temperature For Closed Loop Fuel System, Injection, Ignition System, Exhaust Gas Leakage, Open/Short HO2S Circuit Or HO2S
P0130 (1) (2) Heated Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 1) HO2S Or Fuel Trim Malfunction
P0133 (1) (2) Heated Oxygen Sensor Circuit Slow Response (Bank 1, Sensor 1) HO2S
P0135 (1) (2) Heated Oxygen Sensor Heater Circuit Malfunction (Bank 1, Sensor 1) Open/Short In Heater Circuit, HO2S Or ECM
P0136 (1) (2) Heated Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 2) HO2S
P0141 (1) (2) Heated Oxygen Sensor Heater Circuit Malfunction (Bank 1, Sensor 2) Open/Short In Heater Circuit, HO2S Or ECM
P0150 (1) (2) Heated Oxygen Sensor Circuit Malfunction (Bank 2, Sensor 1) HO2S Or Fuel Trim Malfunction
P0153 (1) (2) Heated Oxygen Sensor Circuit Slow Response (Bank 2, Sensor 1) HO2S
P0155 (1) (2) Heated Oxygen Sensor Heater Circuit Malfunction (Bank 2, Sensor 1) Open/Short In Heater Circuit, HO2S Or ECM
P0156 (1) (2) Heated Oxygen Sensor Circuit Malfunction (Bank 2, Sensor 2) HO2S
P0161 (1) (2) Heated Oxygen Sensor Heater Circuit Malfunction (Bank 2, Sensor 2) Open/Short In Heater Circuit, HO2S Or ECM
P0171 (1) System Too Lean (Fuel Trim) Air Hose, Incorrect Fuel Pressure, Injector Blockage, HO2S, MAF Sensor or ECT Sensor
P0172 (1) System Too Rich (Fuel Trim) Incorrect Fuel Pressure, Injector Leak Or Blockage, HO2S, MAF Sensor or ECT Sensor
P0300  Random Misfire Detected Ignition, Injector, Incorrect Fuel Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0301 (1) Cylinder No. 1 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0302 (1) Cylinder No. 2 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0303 (1) Cylinder No. 3 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0304 (1) Cylinder No. 4 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0305 (1) Cylinder No. 5 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0306 (1) Cylinder No. 6 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0307 (1) Cylinder No. 7 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0308 (1) Cylinder No. 8 Misfire Detected Ignition, Injector, Incorrect Fuel, Pressure, Compression, Valve Clearance, Valve Timing, MAF Sensor, ECT Sensor, Open/Short Circuit, Loose Connector Or ECM
P0325  Knock Sensor No. 1 Circuit Malfunction Open/Short Circuit, Loose Sensor Or ECM
P0330  Knock Sensor No. 2 Circuit Malfunction Open/Short Circuit, Loose Sensor Or ECM
P0335 (1) Crankshaft Position (CKP) Sensor Circuit Malfunction Open/Short Circuit, CKP Sensor, Starter Or ECM
P0340 (1) Camshaft Position (CMP) Sensor Circuit Malfunction Open/Short Circuit, CMP Sensor, Starter Or ECM
P0420 (1) Catalyst System Efficiency Below Threshold Catalytic Converter, Open/Short HO2S Circuit Or HO2S
P0430 (1) Catalyst System Efficiency Below Threshold Catalytic Converter, Open/Short HO2S Circuit Or HO2S
P0440 (1) EVAP System Malfunction Vapor Pressure Sensor Or Circuit, Charcoal Canister, Gas Cap, Fuel Tank Or Faulty Vacuum Circuit
P0441 (1) Incorrect EVAP Purge Flow Open/Short EVAP VSV Circuit, Vapor Pressure Sensor Or Circuit, Charcoal Canister Or Faulty Vacuum Circuit
P0446 (1) EVAP Vent Control Malfunction Open/Short EVAP VSV Circuit, Vapor Pressure Sensor Or Circuit, Charcoal Canister Or Faulty Vacuum Circuit
P0450  EVAP Pressure Sensor Malfunction Open/Short Vapor Pressure Sensor Circuit, Vapor Pressure Sensor Or ECM
P0451  EVAP Pressure Sensor Range/Performance Open/Short Vapor Pressure Sensor Circuit, Vapor Pressure Sensor Or ECM
P0500 (1) Vehicle Speed Sensor Malfunction Vehicle Speed Sensor Or Circuit, VSS Or ECM
P0505 (1) Idle Control System Malfunction Electric Throttle Control System Or Loose Intake Air Hose
P1120  Accelerator Pedal Position (APP) Sensor Circuit Malfunction Open/Short Circuit, APP Sensor Or ECM
P1121  Accelerator Pedal Position (APP) Sensor Range/Performance APP Sensor Or ECM
P1125  Throttle Control Motor Circuit Fault Open/Short Circuit, Throttle Control Motor Or ECM
P1126  Magnetic Clutch Circuit Fault Open/Short Circuit, Magnetic Clutch Or ECM
P1127  Electronic Throttle Control System (ETCS) Fault Open ETCS Power Circuit Or ECM
P1128  Throttle Control Motor Lock Fault Throttle Control Motor, Throttle Body Or ECM
P1129  Electronic Throttle Control System (ETCS) Fault ETCS Or ECM
P1200 (1) Fuel Pump Relay Circuit Malfunction Open/Short Relay Circuit, Fuel Pump Relay Or ECM
P1300  Ignitor Circuit Malfunction (No. 1) Open/Short Ignitor Circuit To ECM, Ignitor, Coil/Igniter Or ECM
P1305  Ignitor Circuit Malfunction (No. 2) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1310  Ignitor Circuit Malfunction (No. 3) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1315  Ignitor Circuit Malfunction (No. 4) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1320  Ignitor Circuit Malfunction (No. 5) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1325  Ignitor Circuit Malfunction (No. 6) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1330  Ignitor Circuit Malfunction (No. 7) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1335  Crankshaft Position (CKP) Sensor Circuit Open/Short CKP Sensor Circuit, CKP Sensor Or ECM
P1340  Ignitor Circuit Malfunction (No. 8) Open/Short Ignitor Circuit To ECM, Ignitor, Coil Or ECM
P1345  Variable Valve Timing (VVT) Sensor Circuit Malfunction Open/Short VVT Sensor Circuit, VVT Sensor Or ECM
P1346  Variable Valve Timing (VVT) Sensor Circuit Range/Performance Mechanical Problem (Timing Belt) Or ECM
P1349  Variable Valve Timing (VVT) System Valve Timing, Oil Control Valve, VVT Controller Or ECM
P1350  Variable Valve Timing (VVT) Sensor Circuit Malfunction Open/Short VVT Sensor Circuit, VVT Sensor Or ECM
P1351  Variable Valve Timing (VVT) Sensor Circuit Range/Performance Mechanical Problem (Timing Belt) Or ECM
P1354  Variable Valve Timing (VVT) System Valve Timing, Oil Control Valve, VVT Controller Or ECM
P1520 (1) Stoplight Switch Signal Malfunction Short Circuit, Stoplight Switch Or ECM
P1565 (3) Cruise Control Main Switch Circuit Malfunction Open/Short Cruise Control Switch Circuit, Cruise Control Switch Or ECM
P1600  ECM BATT Malfunction ECM Power Source Circuit Or ECM
P1633  ECM Malfunction ECM
P1656  Oil Control Valve (OCV) Circuit Fault (Bank 1) Open/Short OCV Circuit, OCV (Bank 1) Or ECM
P1663  Oil Control Valve (OCV) Circuit Fault (Bank 2) Open/Short OCV Circuit, OCV (Bank 2) Or ECM
P1780 (1) Park/Neutral Position Switch Malfunction Park/Neutral Position Switch/Circuit Or ECM
(1) Two-trip detection logic code. For more information, see DETECTION LOGIC  under INTRODUCTION.
(2) Bank No. 1 refers to bank that includes cylinder No. 1. Bank No. 2 refers to bank without cylinder No. 1. Sensor No. 1 refers to sensor closest to engine block.
(3) This DTC applies to cruise control system. See CRUISE CONTROL SYSTEMS - EXCEPT ES300 article in ACCESSORIES & EQUIPMENT.
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