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Home >> Buick >> 2003 >> Century Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls Self-Diagnostics - 3.1L Engine >> Diagnostic Trouble Code Definitions
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Diagnostic Trouble Code Definitions

NOTE: Use of Tech 2® or generic OBD-II scan tool is required to retrieve DTCs. Refer to user reference manual supplied using scan tool.
DIAGNOSTIC TROUBLE CODE DEFINITIONS

DTC (1) Definition (2) Code Type
BXXXX Body Control DTC (3)
CXXXX Suspension/Brake DTC (3)
P0030  HO2S 1 Heater Control Circuit B
P0101  MAF Sensor Performance B
P0102 (4) MAF Sensor Circuit - Low Frequency (Century & Grand Prix) B
P0103  MAF Sensor Circuit - High Frequency B
P0107  Manifold Absolute Pressure Sensor Circuit - Low Voltage B
P0108  Manifold Absolute Pressure Sensor Circuit - High Voltage B
P0112  Intake Air Temperature Sensor Circuit - Low Voltage B
P0113  Intake Air Temperature Sensor Circuit - High Voltage B
P0116  Engine Coolant Temperature Sensor Circuit B
P0117  Engine Coolant Temperature Sensor Circuit - Low Voltage B
P0118  Engine Coolant Temperature Sensor Circuit - High Voltage B
P0121  Throttle Position Sensor Circuit Performance B
P0122  Throttle Position Sensor Circuit - Low Voltage B
P0123  Throttle Position Sensor Circuit - High Voltage B
P0125  Engine Coolant Temperature Insufficient For Closed Loop Fuel Control B
P0128  Engine Coolant Temperature Below Thermostat Regulating Temperature B
P0130  HO2S 1 Circuit Closed Loop Performance B
P0131  HO2S 1 Circuit - Low Voltage B
P0132  HO2S 1 Circuit - High Voltage B
P0133  HO2S 1 - Slow Response B
P0134  HO2S 1 Circuit - Insufficient Activity B
P0135  HO2S 1 Heater Performance B
P0137  HO2S 2 Circuit - Low Voltage B
P0138  HO2S 2 Circuit - High Voltage B
P0140  HO2S 2 Circuit - Insufficient Activity B
P0141  HO2S 2 Heater Performance B
P0171  Fuel Trim System Lean B
P0172  Fuel Trim System Rich B
P0201-P0206  Injector Control Circuit B
P0218 (5) Transmission Fluid Overtemperature C
P0230  Fuel Pump Relay Control Circuit - Voltage Incorrect C
P0300  Engine Misfire Detected (6)
P0325  Knock Sensor Performance B
P0327  Knock Sensor Circuit B
P0336  Crankshaft Position Sensor Performance B
P0341  Camshaft Position Sensor Performance B
P0401  EGR Flow Insufficient A
P0403  EGR Solenoid Control Circuit B
P0404  EGR Open Position Performance B
P0405  EGR Position Sensor Circuit - Low Voltage B
P0420  Catalyst System - Low Efficiency A
P0440  Evaporative Emission System B
P0442  Evaporative Emission Control System - Small Leak Detected A
P0443  EVAP Purge Solenoid Control Circuit B
P0446  EVAP Vent System Performance B
P0449  EVAP Vent Solenoid Control Circuit B
P0452  Fuel Tank Pressure Sensor Circuit - Low Voltage A
P0453  Fuel Tank Pressure Sensor Circuit - High Voltage A
P0462 (7) Fuel Level Sensor Circuit - Low Voltage C
P0463 (7) Fuel Level Sensor Circuit - High Voltage C
P0480 (8) Cooling Fan Low Speed Relay Control Circuit B
P0481 (8) Cooling Fan High Speed Relay Control Circuit B
P0502 (5) Vehicle Speed Sensor Circuit - Low Input B
P0503 (5) Vehicle Speed Sensor Circuit Intermittent B
P0506  Idle Speed Low B
P0507  Idle Speed High B
P0530 (9) A/C Refrigerant Pressure Sensor Circuit C
P0560 (10) System Voltage C
P0601-P0607, P1600, P1621, P1627, P1680, P1681, P1683 Or P2610  ECU Malfunction A
P0620 (10) Generator "F" Terminal Control Circuit C
P0650  MIL Control Circuit B
P0711 (5) Transmission Fluid Temperature Sensor Circuit Range/Performance C
P0712 (5) Transmission Fluid Temperature Sensor Circuit - Low Input C
P0713 (5) Transmission Fluid Temperature Sensor Circuit - High Input C
P0716 (5) Input Speed Sensor Circuit - Intermittent B
P0717 (5) Input Speed Sensor Circuit - Low Input B
P0719 (5) Brake Switch Circuit - Low Input C
P0724 (5) Brake Switch Circuit - High Input C
P0730 (5) Incorrect Gear Ratio C
P0741 (5) TCC System Stuck Off B
P0742 (5) TCC System Stuck On B
P0748 (5) Pressure Control Solenoid Circuit Electrical Malfunction C
P0751 (5) 1-2 Shift Solenoid Valve Performance - No First Or Fourth Gear B
P0752 (5) 1-2 Shift Solenoid Valve Performance - No Second Or Third Gear B
P0753 (5) 1-2 Shift Solenoid Circuit Fault B
P0756 (5) 2-3 Shift Solenoid Valve Performance - No First or Second Gear A
P0757 (5) 2-3 Shift Solenoid Valve Performance - No Third Or Fourth Gear A
P0758 (5) 2-3 Shift Solenoid Circuit Fault A
P1106  MAP Sensor Circuit Intermittent - High Voltage C
P1107  MAP Sensor Circuit Intermittent - Low Voltage C
P1111  IAT Sensor Circuit Intermittent - High Voltage C
P1112  IAT Sensor Circuit Intermittent - Low Voltage C
P1114  ECT Sensor Circuit Intermittent - Low Voltage C
P1115  ECT Sensor Circuit Intermittent - High Voltage C
P1121  TP Sensor Circuit - Intermittent High Voltage C
P1122  TP Sensor Circuit Intermittent - Low Voltage C
P1133  HO2S 1 - Insufficient Switching B
P1134  HO2S 1 Transition Time Ratio B
P1189 (7) Engine Oil Pressure Switch Circuit C
P1336  Crankshaft Position System Variation Not Learned A
P1351  Ignition Coil Control Circuit - High Voltage B
P1352  Ignition Bypass Circuit - High Voltage B
P1361  IC Circuit - Low Voltage B
P1362  Ignition Control Circuit - Low Voltage B
P1374  CKP High To Low Resolution Frequency Correlation B
P1380  Misfire Detected - Rough Road Data Not Available (Century & Malibu) C
P1381  Misfire Detected No EBTCM/PCM Serial Data (Century & Malibu) C
P1404  EGR Closed Position Performance B
P1441  Evaporative Emission System Flow During Non-Purge A
P1546 (9) A/C Clutch Relay Control Circuit C
P1554 (11) Cruise Control Feedback Circuit C
P1585 (11) Cruise Control Inhibit Output Circuit C
P1626 (12) Theft Deterrent Fuel Enable Signal Not Correct C
P1629 (12) Theft Deterrent Learn Mode Active C
P1630 (12) Theft Deterrent Fuel Enable Signal Not Correct C
P1631 (12) Theft Deterrent Fuel Enable Signal Not Correct C
P1632 (12) Theft Deterrent Fuel Disable Signal Received C
P1635  5-volt Reference 1 Circuit (Century & Grand Prix) B
P1635  5-volt Reference 1 Circuit (Malibu) B
P1639   
5-Volt Reference 2 Circuit (Century)		 B
P1639   
5-Volt Reference 2 Circuit (Grand Prix & Malibu)		 B
P1640  PCM Output "A" Circuit C
P1650  PCM Output "B" Circuit C
P1660  PCM Output "C" Circuit C
P1670  PCM Output "D" Circuit C
P1811 (5) Maximum Adapt & Long Shift C
P1814 (5) Torque Converter Overstressed C
P1815 (5) Transmission Fluid Pressure Valve Position Switch - Starts In Wrong Range C
P1816 (5) Transmission Fluid Pressure Valve Position Switch Indicates Park/Neutral With Drive Ratio C
P1817 (5) Transmission Fluid Pressure Valve Position Switch-Reverse With Drive Ratio C
P1818 (5) Transmission Fluid Pressure Valve Position Switch Indicates Drive Without Drive Ratio C
P1819 (5) Internal Mode Switch - No Start/Wrong Range C
P1820 (5) Internal Mode Switch "A" Circuit - Low Voltage C
P1822 (5) Internal Mode Switch "B" Circuit - High Voltage C
P1823 (5) Internal Mode Switch "P" Circuit - Low Voltage C
P1825 (5) Internal Mode Switch - Invalid Range C
P1826 (5) Internal Mode Switch "C" Circuit - High Voltage C
P1860 (5) TCC PWM Solenoid Circuit B
P1887 (5) TCC Release Switch Circuit B
UXXXX Communication DTC (3)
(1) DTC definitions may vary depending on vehicle and/or engine configuration.
(2) See CODE TYPES  under ON-BOARD DIAGNOSTICS.
(3) See appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
(4) For Century and Grand Prix only. For Malibu, go to DTC P0102: MAF SENSOR CIRCUIT - LOW VOLTAGE (MALIBU) 
(5) See appropriate DIAGNOSIS article in AUTOMATIC TRANSMISSIONS.
(6) DTC is a type "A" if it is catalyst related or a type "B" if it is emissions related.
(7) See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT.
(8) See appropriate ELECTRIC COOLING FANS ARTICLE in ENGINE COOLING.
(9) See appropriate A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
(10) See appropriate GENERATORS & REGULATORS article in ELECTRICAL.
(11) See appropriate CRUISE CONTROL SYSTEMS article in ACCESSORIES & EQUIPMENT.
(12) See appropriate ANTI-THEFT SYSTEMS article in ACCESSORIES & EQUIPMENT.
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