OBDII GMC Code Definitions.

Be sure to double check the codes. Anything P1000 to P1999 or P3000 to P3400 will be Manufacturer specific and may not match the ones listed here. Check specific manufacturer pages on the site, as some of them, we list the OBD2 codes on those pages for those specific vehicles.

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GMC Codes
Trouble CodeFault LocationProbable Cause
P1000 – P1099 (Fuel and air metering and auxiliary emission control)
P1093Fuel rail pressure (FRP) sensor, command/actual fuel pressure -signal variationWiring, poor connections, FRP sensor
P1094Fuel rail pressure (FRP) sensor -signal out ofrangeWiring, poor connections, FRP sensor
P1100 – P1199 (Fuel and air metering)
P1101Intake airflow -incorrectWiring, mechanical fault, engine coolant temperature (ECT) sensor, barometric pressure (BARO) sensor, intake air temperature (IAT) sensor, manifold absolute pressure (MAP) sensor,mass air flow (MAF) sensor, throttle position (TP) switch
P1106Manifold absolute pressure (MAP) sensor voltage high, intermittentWiring open circuit/short circuit to positive, poor connections
P1107Manifold absolute pressure (MAP) sensor voltage low, intermittentWiring short circuit to ground, poor connections
P1111Intake air temperature (IAT) sensor -voltage high,intermittentWiring open circuit/short to positive, poor connections
P1112Intake air temperature (IAT) sensor -voltage low,intermittentWiring short circuit to ground
P1114Engine coolant temperature (ECT) sensor voltage low, intermittentWiring short circuit to ground, poor connections
P1115Engine coolant temperature (ECT) sensor voltage high, intermittentWiring open circuit/short to positive, poor connections
P1120Throttle motor position sensor 1 -circuit malfunctionWiring, throttle control module
P1121Throttle position (TP) sensor -voltage high, intermittentWiring open circuit/short to positive, poor connections
P1122Throttle position (TP) sensor -voltage low,intermittentWiring open circuit/short to ground, poor connections
P1125Accelerator pedal position (APP) sensor 1/2/3 -signal variationWiring, APP sensor, ECM
P1133Oxygen sensor (02S)/heated oxygen sensor(H02S) 1, bank 1 -insufficient switchingWiring, exhaust system leaking, 02S/H02S
P1134Heated oxygen sensor (H02S) 1, bank 1 slow responseWiring, oxygen sensor heater, exhaust system leaking, H02S
P1137Heated oxygen sensor (H02S) 2, bank 1 voltagelowWiring, exhaust system leaking, H02S
P1138Heated oxygen sensor (H02S) 2, bank 1 voltage highWiring, H02S
P1153Heated oxygen sensor (H02S) 1, bank 2insufficient switchingWiring, oxygen sensor heater, exhaust system leaking, H02S
P1154Heated oxygen sensor (H02S) 1, bank 2 slow responseWiring, oxygen sensor heater, exhaust system leaking, H02S
P1171Fuel system -lean during accelerationFuel filter, fuel pump, H02S, injectors
P1172Fuel level sensors, primary & secondary sensor no fuel level change during fuel transfer from secondary to primary tankWiring, secondary fuel pump/relay, fuel level sensors
P1174Heated oxygen sensor (H02S) 1, bank 1 mixture variation between cylindersIntake/exhaust leak/blockage, mechanical fault, ignition control, H02S
P1175Heated oxygen sensor (H02S) 1, bank 2 mixture variation between cylindersIntake/exhaust leak/blockage, mechanical fault, ignition control, H02S
P1191Intake manifold system -air leakIntake hose pipe connections, EGR system, ECM
P1200 – P1299 (Fuel and air metering – injector circuit)
P1214Fuel injection pump timing -out of rangeFuel injection pump timing incorrectly set, CKP sensor, ECM
P1216Fuel injection duration -pulse width signal shorter than expectedWiring, fuel injection duration control solenoid, fuel injection pump control module, ECM
P1217Fuel injection duration -pulse width signal longerthan expectedWiring, fuel injection duration control solenoid, fuel injection pump control module, ECM
P1218Fuel injection pump calibration resistor-circuit malfunctionWiring, calibration resistor
P1220Throttle motor position sensor 1 -circuit malfunctionWiring, throttle control module
P1221Fuel pump, run signal -circuit malfunction
Throttle motor position sensor 2 -circuit malfunction		Wiring, engine oil pressure switch, fuel pump relay Wiring, throttle control module
P1222Fuel pump, run signal:”” circuit malfunctionWiring, engine oil pressure switch, fuel pump relay
P1223Injector 1 -circuit malfunctionWiring, injector, FICM
P1224Injector 1 -circuit malfunctionWiring, injector, ECM
P1226Injector 2 -circuit malfunctionWiring, injector, FICM
P1227Injector 2 -circuit malfunctionWiring, injector, ECM
P1229Injector 3 -circuit malfunctionWiring, injector, FICM
P122AInjector 3 -circuit malfunctionWiring, injector, ECM
P1232Injector 4 -circuit malfunctionWiring, injector, FICM
P1233Injector 4 -circuit malfunctionWiring, injector, ECM
P1235Injector 5 -circuit malfunctionWiring, injector, FICM
P1236Injector 5 -circuit malfunctionWiring, injector, ECM
P1238Injector 6 -circuit malfunctionWiring, injector, FICM
P1239Injector 6 -circuit malfunctionWiring, injector, ECM
P1241Injector 7 -circuit malfunctionWiring, injector, FICM
P1242Injector 7 -circuit malfunctionWiring, injector, ECM
P1244Injector 8 -circuit malfunctionWiring, injector, FICM
P1247Injector 8 -circuit malfunctionWiring, injector, ECM
P1255Fuel pump control module -driver over-temperatureFuel pump control module
P1258Engine overheatingCooling system, ECT sensor
P1261Injectors 1, 4, 6 & 7 -high voltageWiring, injector(s), ECM
P1262Injectors 2, 3, 5 & 8 -high voltageWiring, injector(s), ECM
P1270Engine control module (ECM). APP sensor signal -analogue/digital process malfunctionEngine control module (ECM)
P1271Accelerator pedal position (APP) sensor 1/2 signal variationWiring, APP sensor, ECM
P1272Accelerator pedal position (APP) sensor 2/3signal variationWiring, APP sensor, ECM
P1273Accelerator pedal position (APP) sensor 1/3signal variationWiring, APP sensor, ECM
P1275Accelerator pedal position (APP) sensor 1 circuitmalfunctionWiring, APP sensor, ECM
P1276Accelerator pedal position (APP) sensor 1 range performanceWiring, APP sensor, ECM
P1277Accelerator pedal position (APP) sensor 1voltage lowWiring, APP sensor, ECM
P1278Accelerator pedal position (APP) sensor 1 voltage highWiring, APP sensor, ECM
P1280Accelerator pedal pOSition (APP) sensor 2 circuit malfunctionWiring, APP sensor, ECM
P1281Accelerator pedal position (APP) sensor 2 range performanceWiring, APP sensor, ECM
P1282Accelerator pedal position (APP) sensor 2 voltage lowWiring, APP sensor, ECM
P1283Accelerator pedal position (APP) sensor 2 voltage highWiring, APP sensor, ECM
P1285Accelerator pedal position (APP) sensor 3 circuit malfunctionWiring, APP sensor, ECM
P1286Accelerator pedal position (APP) sensor 3 range performanceWiring, APP sensor, ECM
P1287Accelerator pedal position (APP) sensor 3 voltage lowWiring, APP sensor, ECM
P1288Accelerator pedal position (APP) sensor 3 voltage highWiring, APP sensor, ECM
P1293Injector control module -circuit malfunction bank 1Injector control module
P1294Injector control module -circuit malfunction bank 2Injector control module
P1295Injector control module -circuit malfunction bank 1Injector control module
P1296Injector control module -circuit malfunction bank 2Injector control module
P1300 – P1399 (Ignition system or misfire)
P1336Crankshaft position (CKP) sensor -variation not leamedLearning procedure not performed
P1345Crankshaft position (CKP) sensor/camshaftposition (CMP) sensor -signal variationWiring, CKP sensor, CMP sensor
P1351Ignition control system, coil -voltage highWiring open circuit, ICM, ECM
P1361Ignition control system, IC circuit -voltage lowWiring, circuit short circuit to ground, poor connections, ICM, ECM
P1380Antilock brake system (ABS)/traction controlsystem (TCS), rough road signal to ECM -malfunctionABSfTCS trouble code(s) stored
P1381Antilock brake system (ABS)/traction control system (TCS), rough road signal to ECM -nocommunicationWiring, poor connections, ABSfTCS
P1400 – P1499 (Emission control)
P1400Cold start emission control -malfunctionIntake/exhaust leak/blockage, mechanical fault, idle speed control (ISC) system, ignition control, engine coolant temperature (ECT) sensor, H02S
P1404Exhaust gas recirculation (EGR) valve -not fully closingWiring, poor connections, EGR valve position sensor, EGR solenoid
P1406Exhaust gas recirculation (EGR) valve position sensor range performanceWiring, EGR valve tight/sticking, EGR valve position sensor
P1409Exhaust gas recirculation (EGR) systemmalfunctionWiring, vacuum pipes, EGR vacuum sensor, EGR valve
P1415Secondary air injection (AIR) system, bank 1Wiring, hoses blocked/leaking. AIR valve
P1416Secondary air injection (AIR) system, bank 2Wiring. hoses blockedfleaking, AIR valve
P1431Fuel level sensor, secondary -circuit malfunctionWiring, fuel level sensor
P1432Fuel level sensor -low voltageWiring open circuit, fuel level sensor
P1433Fuel level sensor -high voltageWiring short circuit to positive, fuel level sensor
P1441Evaporative emission (EVAP) system -leakdetectedHose connection(s), EVAP canister, EVAP canister purge valve
P1442Evaporative emission (EVAP) system vacuum switch -circuit malfunctionHoses blockedfleaking, wiring, EVAP canister, ECM
P1481Engine coolant fan speed sensor -signal lossWiring, engine coolant fan speed sensor
P1482Engine coolant fan clutch solenoid -circuit malfunctionWiring, engine coolant fan clutch solenoid, engine coolant fan clutch solenoid relay
P1484Engine coolant fan speed/engine speed -signal variationWiring, engine coolant fan clutch, engine coolant fan speed sensor
P1500 – P1599 (Vehicle or idle speed control)
P1504Engine control module (ECM), vehicle speed sensor (VSS) output signal -circuit malfunctionWiring, poor connections, ASS, ECM
P1508Idle air control (lAC) valve -low rpmWiring open circuit/short circuit to ground/short circuit to positive, lAC valve, throttle valve tight/sticking
P1509Idle air control (lAC) valve -high rpmWiring open circuit/short circuit to ground/short circuit to positive, lAC valve, throttle valve tight/sticking
P1512Throttle command/actual throttle position -signals out of rangeWiring, throttle valve sticking, throttle control module
P1514Throttle control unit, intake air flow -excessiveThrottle control unit, MAP sensor, CMP sensor signal, ECM
P1515Throttle command/actual throttle position -signal variationWiring, throttle valve sticking, throttle control module
P1516Throttle command/actual throttle position -signal variationWiring, throttle valve sticking, throttle control module
P1517Throttle control module -malfunctionThrottle control module
P1518Throttle control module/engine control module (ECM) -communication malfunctionWiring, throttle control module, ECM
P1520Park/neutral position (PNP) switch -circuit malfunctionWiring short circuit to ground, PNP switch incorrectly adjusted
P1523Throttle control unit, throttle position during battery saving modeThrottle valve movement restricted, throttle control unit, ECM
P154AIntake air heater -feedback circuitWiring, glow plug control module, intake air heater
P154BIntake air heater -voltage signal circuitWiring, glow plug control module, intake air heater
P154CIntake air heater -current signal circuitWiring, glow plug control module, intake air heater
P154DIntake air heater -temperature signal circuitWiring, glow plug control module, intake air heater
P1550System voltage lowWiring, battery, alternator
P1571Traction control system (TCS), torque request signal -malfunctionWiring, poor connections, ABSITCS
P1574Brake pedal position (BPP) switch, voltage highWiring, ABS
P1600 – P1699 (ECM – computer output circuit)
P1600Engine control module (ECM) -malfunctionECM
P1601CAN data bus, engine control module (ECM)/ anti lock brake system (ABS)/traction control system (TCS)/instrumentation control module/ diagnostic control module some communication lostWiring, poor connections, ECM, ABSITCS,diagnostic control module, instrumentation control module
P1602Engine control module (ECM) to antilock brake system (ABS)/traction control system (TCS), CAN data bus -communication failureWiring, poor connections, ABS control module
P1621Engine control module (ECM) -memory performanceECM
P1626Engine control module (ECM) -fuel enable signal lostWiring, poor connections, immobilizer control module, ECM
P1627Engine control module (ECM) -malfunctionECM
P1630Engine control module (ECM), immobilizer code -leaming modeECM immobilizer code programming not completed
P1631Engine control module (ECM) -incorrect immobilizer code
System voltage low
Engine control module (ECM) -fuel disable signal received		Incorrect key, immobilizer code not programmed Wiring, battery, alternator Fuses, BCM, immobilizer code
P1633Engine control module (ECM ), ignition supply voltageFuse, wiring open circuit, ECM
P1634Engine control module (ECM) -ignition supply voltage -voltage lowWiring open circuit, ECM
P1635Engine control module (ECM), sensor supply voltage -circuit malfunctionWiring, poor connections, TP sensor, MAP sensor, EGR valve position sensor, ECM
P1637Alternator warning lamp, control signal -circuit malfunctionWiring, instrument panel, ECM
P1638Alternator ‘F’ terminal -circu it malfunctionWiring open circuit/short circuit to ground,alternator, ECM
P1639Engine control module (ECM), sensor supply voltage -circuit malfunctionWiring, poor connections, FTP sensor, ECM
P1641Malfunction indicator lamp (MIL) -circuitmalfunctionWiring, fuses, MIL
P1643Glow plug waming lamp -circuit malfunctionWiring, glow plug warning lamp, ECM
P1644Traction control system (TCS), delivered torque signal -malfunctionWiring, poor connections, ECM
P1653Exhaust gas recirculation (EGR) vent valve circuit malfunctionWiring, poor connections, EGR vent valve, ECM
P1654Service throttle soon warning lamp -circuit malfunctionWiring, fuses, service throttle soon warning lamp
P1655Exhaust gas recirculation (EGR) control valve -circuit malfunctionWiring, poor connections, EGR control valve,ECM
P1656Turbocharger (TC) wastegate regulating valve -circuit malfunctionWiring, TC wastegate regulating valve, ECM
P1658Fuel injector control module (FICM) malfunctionFICM
P1665Fuel level sensor -signal malfunctionWiring short circuit to positive, fuel level sensor
P1668Alternator ‘l’ terminal -circuit malfunctionWiring, voltage regulator, alternator, ECM
P1680Engine control module (ECM) -malfunctionECM
P1681Engine control module (ECM) -malfunctionECM
P1682Engine control module (ECM) -ignition powersupply less than 10 VWiring, ECM
P1683Engine control module (ECM) -malfunctionECM
P1687Fuel injector control module (FICM) -stuck onECM, FICM
P1688Engine control module (ECM), torque reduction signal -out of rangeWiring TCM, ECM
P1689Traction control system (TCS), delivered torquesignal -malfunctionWiring, poor connections, ECM
P16F3Engine control module -redundant memoryperformanceWiring, ECM
P1700 – P1799 (Transmission)
P1779Engine control module (ECM), torque reduction signal -out of rangeWiring TCM, ECM
P1781Transmission control module (TCM), MIL requestsignal -voltage high/lowWiring TCM, ECM
P1800 – P1899 (Transmission)
P1810Transmission gear pressure switch, signal -circuit malfunctionWiring open circuit/short circuit to ground,reverse/D1/D2/D3/D4 gear pressure switch(es), ECM
P1811Shift time too long -adaptation limit reachedFluid level low, transmission mechanical fault
P1812Transmission fluid temperature (TFT) highTransmission mechanical fault, towing weight limit exceeded
P1815Transmission fluid pressure (TFP) switch -invalid gear selectionWiring, selector lever linkage incorrectly adjusted, TFP switch, ECMITCM
P1816Transmission fluid pressure (TFP) switch -invalid gear selectionWiring, selector lever linkage incorrectly adjusted, TFP switch, ECMITCM
P1860Torque converter clutch (TCC) solenoid, pulsewidth modulation (PWM) -circuit malfunctionWiring open circuit/short circuit to ground, TCC solenoid, ECM
P1864Torque converter clutch (TCC) solenoid -circuit malfunctionWiring open circuit/short circuit to ground, TCC solenoid, ECM
P1870Torque converter clutch (TCC) -slip speed excessiveTransmission fluid level, wiring, TCC solenoid, ECM
P1875Transmission, 4WD low selection signal -circuit malfunctionWiring, transmission, four wheel drive control module, ECM
P1886Transmission 3rd-2nd control solenoid -circuitmalfunctionWiring, control solenoid, ECM
P3400Cylinder cut-out system -malfunctionWiring, intake system leaking, mechanical fault, MAF sensor, MAP sensor, TP sensor, ECM
P3401Cylinder cut-out solenoid, cylinder 1 malfunctionWiring, cylinder cut-out solenoid, mechanical fault, ECM
P3425Cylinder cut-out solenoid , cylinder 4 malfunctionWiring, cylinder cut-out solenoid, mechanical fault, ECM
P3441Cylinder cut-out solenoid, cylinder 6 malfunctionWiring, cylinder cut-out solenoid, mechanical fault, ECM
P3449Cylinder cut-out solenoid, cylinder 7 malfunctionWiring, cylinder cut-out solenoid, mechanical fault,ECM
U1000 – U2000 (Manufacturer defined, common defination listed)
U1026Transmission control module (TCM)/four wheeldrive control module, CAN data bus -communication malfunctionWiring, BCM
U1041Antilock brake system (ABS)/traction controlsystem (TCS), CAN data bus -communicationmalfunctionWiring, ABSITCS control module
U1064Body control module (BCM)/immobilizer controlmodule, CAN data bus -communication malfunctionWiring, BCM, immobilizer control module
U1192Engine control module (ECM)limmobilizer control module, CAN data bus -signal malfunctionWiring, immobilizer control module, ECM
U1193Engine control module (ECM)limmobilizer control module, CAN data bus -signal malfunctionWiring, immobilizer control module, ECM
U1800Engine control module (ECM)/fuel injector control module (FICM), CAN data bus -communication malfunctionWiring, FICM, ECM
U2104Engine control module (ECM)/transmission control module (TCM)/Fuel injector control module (FICM), CAN data bus communication malfunctionWiring, TCM, FICM, ECM