2001 Buick Regal LSFACTORY OEM SERVICE PROCEDURE

Diagnostic Trouble Code Definitions

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

DTC (1) Definition (2) Code Type
BXXXX Body Control Systems Malfunction (3)
CXXXX Chassis Control Systems Malfunction (3)
P0101  MAF System Performance B
P0102  MAF Sensor Circuit - Low Frequency B
P0103  MAF Sensor Circuit - High Frequency B
P0107  MAP Sensor Circuit - Low Voltage B
P0108  MAP Sensor Circuit - High Voltage B
P0112  IAT Sensor Circuit - Low Voltage B
P0113  IAT Sensor Circuit - High Voltage B
P0117  ECT Sensor Circuit - Low Voltage B
P0118  ECT Sensor Circuit - High Voltage B
P0121  TP Sensor Performance B
P0122  TP Sensor Circuit - Low Voltage B
P0123  TP Sensor Circuit - High Voltage B
P0125  ECT Excessive Time To Enter Closed Loop Fuel Control B
P0128  ECT Less Than Thermostat Regulating Temperature B
P0130  HO2S Low Activity - Bank 1, Sensor 1 B
P0131  HO2S Circuit Low Voltage - Bank 1, Sensor 1 B
P0132  HO2S Circuit High Voltage - Bank 1, Sensor 1 B
P0133  HO2S Slow Response - Bank 1, Sensor 1 B
P0134  HO2S Circuit Insufficient Activity - Bank 1, Sensor 1 B
P0135  HO2S Heater Performance - Bank 1, Sensor 1 B
P0137  HO2S Circuit Low Voltage - Bank 1, Sensor 2 B
P0138  HO2S Circuit High Voltage - Bank 1, Sensor 2 B
P0140  HO2S Circuit Insufficient Activity - Bank 1, Sensor 2 B
P0141  HO2S 2 Heater Performance - Bank 1, Sensor 2 B
P0171  Fuel Trim System Lean - Bank 1 B
P0172  Fuel Trim System Rich - Bank 1 B
P0201  Injector No. 1 Control Circuit B
P0202  Injector No. 2 Control Circuit B
P0203  Injector No. 3 Control Circuit B
P0204  Injector No. 4 Control Circuit B
P0205  Injector No. 5 Control Circuit B
P0206  Injector No. 6 Control Circuit B
P0218 (4) Transaxle Fluid Overtemperature C
P0230  Fuel Pump Relay Control Circuit C
P0243  Supercharger Boost Solenoid Control Circuit (Bonneville, Grand Prix, Park Avenue & Regal - VIN 1) C
P0300  Engine Misfire Detected B
P0325  Knock Sensor Module Circuit B
P0327  Knock Sensor Circuit - Bank 1 B
P0332  Knock Sensor Circuit - Bank 2 B
P0336  Crankshaft Position Sensor Circuit B
P0341  Camshaft Position Sensor Performance B
P0401  EGR System Insufficient Flow A
P0403  EGR Solenoid Control Circuit B
P0404  EGR Open Position Performance B
P0405  EGR Position Sensor Circuit - Low Voltage B
P0410  Secondary Air Injection System B
P0412  Secondary Air Injection Solenoid Control Circuit B
P0418  Secondary Air Injection Relay Control Circuit B
P0420  Catalyst System Low Efficiency A
P0440  EVAP System B
P0442  EVAP Control System Small Leak Detected A
P0443  EVAP Purge Solenoid Control Circuit B
P0446  EVAP Vent System Performance B
P0449  EVAP Canister Vent Solenoid Valve Control Circuit B
P0452  Fuel Tank Pressure Sensor Circuit - Low Voltage B
P0453  Fuel Level Pressure Sensor Circuit - High Voltage B
P0462 (5) Fuel Level Sensor Circuit - Low Voltage C
P0463 (5) Fuel Level Sensor Circuit - High Voltage C
P0480  Cooling Fan Relay No. 1 Control Circuit B
P0481  Cooling Fan Relay No. 2 & 3 Control Circuit B
P0502  Vehicle Speed Sensor Circuit - Low Output B
P0503  Vehicle Speed Sensor Circuit - Erratic Output B
P0506  IAC System RPM Low B
P0507  IAC System RPM High B
P0522 (5) Engine Oil Pressure Sensor Circuit - Low Voltage (Bonneville, LeSabre & Park Avenue) C
P0523 (5) Engine Oil Pressure Sensor Circuit - High Voltage (Bonneville, LeSabre & Park Avenue) C
P0530 (6) A/C Refrigerant Pressure Sensor Circuit C
P0560  System Voltage C
P0601  PCM Read Only Memory A
P0602  PCM Not Programmed A
P0603  PCM Long Term Memory Reset N/A
P0604  PCM Random Access Memory N/A
P0605  PCM Programming Read Only Memory N/A
P0606  PCM Internal Performance N/A
P0607  PCM Performance N/A
P0620  Generator Performance C
P0650  Malfunction Indicator Light Control Circuit B
P0656  Fuel Level Output Circuit (Grand Prix) C
P0711 (4) TFT Sensor Circuit Performance C
P0712 (4) TFT Sensor Circuit Low Input C
P0713 (4) TFT Sensor Circuit High Input C
P0716 (4) ISS Circuit Performance B
P0717 (4) ISS Circuit No Signal B
P0719 (4) TCC Brake Switch Circuit Low Input C
P0724 (4) TCC Brake Switch Circuit High Input C
P0730 (4) Incorrect Gear Ratio C
P0741 (4) TCC System Stuck Off B
P0742 (4) TCC System Stuck On A
P0748 (4) Pressure Control Solenoid Electrical Problem C
P0751 (4) 1-2 Shift Solenoid Performance B
P0752 (4) Incorrect Gear Ratio B
P0753 (4) 1-2 Shift Solenoid Electrical Problem B
P0756 (4) 2-3 Shift Solenoid Performance A
P0757 (4) Incorrect Gear Ratio A
P0758 (4) 2-3 Shift Solenoid Electrical Problem A
P1106  MAP Sensor Circuit Intermittent - High Voltage C
P1107  MAP Sensor Circuit Intermittent - Low 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 Insufficient Switching - Bank 1, Sensor 1 B
P1134  HO2S Transition Time Ratio - Bank 1, Sensor 1 B
P1189 (5) Engine Oil Pressure Switch Performance (Impala & Monte Carlo) C
P1336  CKP System Variation Not Learned A
P1351  Ignition Control Circuit - High Voltage B
P1352  Ignition By-Pass Circuit - High Voltage B
P1361  Ignition Control Circuit - Low Voltage B
P1362  Ignition By-Pass Circuit - Low Voltage B
P1374  Crankshaft Position (CKP) High-To-Low Resolution Frequency Correlation B
P1380  Misfire Detected - Rough Road Data Not Available C
P1381  Misfire Detected - No Communication With Brake Control Module C
P1404  EGR Closed Position Performance A
P1441  EVAP System Flow During Non-Purge B
P1536 (6) Engine Coolant Overtemperature - A/C Disabled N/A
P1540 (6) A/C Refrigerant Overpressure - A/C Disabled N/A
P1546 (6) A/C Clutch Relay Control Circuit C
P1554 (7) Cruise Control Feedback Circuit C
P1571 (8) Traction Control System Torque Request Circuit C
P1575  Extended Travel Brake Switch Circuit (Bonneville, LeSabre, Park Avenue & Regal) C
P1585 (7) Cruise Control Inhibit Output Circuit C
P1600  PCM Long Term Memory Reset N/A
P1621  PCM Long Term Memory Performance N/A
P1626 (9) Theft Deterrent Fuel Enable Signal Lost C
P1627  PCM N/A
P1629 (9) Theft Deterrent Fuel Enable Signal Not Received C
P1630 (9) Theft Deterrent Learn Mode C
P1631 (9) Theft Deterrent Start Enable Signal Incorrect C
P1635  5-Volt Reference Circuit "A" Or No. 1 B
P1637 (10) Charging System Light Control Circuit (Grand Prix) C
P1639  5-Volt Reference Circuit "B" Or No. 2 (Bonneville, Impala, Monte Carlo & Regal) B
P1639  5-Volt Reference Circuit "B" Or No. 2 (Grand Prix, LeSabre & Park Avenue) B
P1640  Output Driver Module Circuit No. 1 C
P1650  Output Driver Module Circuit No. 2 C
P1653 (5) Low Engine Oil Level Light Control Circuit (Grand Prix & Regal) C
P1660  Output Driver Module Circuit No. 3 C
P1663 (5) Change Oil Sensor Control Circuit (Grand Prix) N/A
P1670  Output Driver Module Circuit No. 4 C
P1680  PCM N/A
P1681  PCM N/A
P1683  PCM N/A
P1689 (8) Traction Control Delivered Torque Output Circuit C
P1810 (4) Position Switch Circuit Malfunction B
P1811 (4) Maximum Adapt & Long Shift C
P1814 (4) Torque Converter Overstress C
P1819 (4) Transmission Internal Mode Switch - No Start/Wrong Range C
P1820 (4) Transmission Internal Mode Switch Circuit "A" C
P1822 (4) Transmission Internal Mode Switch Circuit "B" C
P1823 (4) Transmission Internal Mode Switch Circuit "P" C
P1825 (4) Transmission Internal Mode Switch - Invalid Range C
P1826 (4) Transmission Internal Mode Switch Circuit "C" C
P1860 (4) TCC PWM Solenoid Electrical Problem B
P1887 (4) TCC Release Switch Circuit Malfunction B
UXXXX Network Comminication System Malfunction (3)
(1) DTC definitions may vary depending on vehicle and/or engine configuration.
(2) See CODE TYPES  under ON-BOARD DIAGNOSTICS.
(3) See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
(4) See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS.
(5) See appropriate ANALOG INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT.
(6) See appropriate MANUAL or AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
(7) See appropriate CRUISE CONTROL SYSTEMS article in ACCESSORIES & EQUIPMENT.
(8) See appropriate ANTI-LOCK/TCS article in BRAKES.
(9) See appropriate ANTI-THEFT SYSTEMS article in ACCESSORIES & EQUIPMENT.
(10) See appropriate GENERATORS & REGULATORS article in STARTING & CHARGING SYSTEMS.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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