| Scan code | Fault location | Probable cause |
| PO,P2,UO | Refer to OBO-II trouble code tables | – |
| P1000 | System readiness test not complete | – |
| P1001 | Self-test | – |
| P1100 | Mass air flow (MAF) sensor -circuit intermittent | Wiring, MAF sensor |
| P1101 | Mass air flow (MAF) sensor -signal malfunction | Wiring, battery, MAF sensor, ECM |
| P1112 | Intake air temperature (IAT) -circuit intermittent | Wiring, IAT sensor, ECM |
| P1114 | Intake air temperature (IAT) sensor 2 -low input | Wiring short circuit to ground, IAT sensor, ECM |
| P1115 | Intake air temperature (IAT) sensor 2 -high input | Wiring, IAT sensor, ECM |
| P1116 | Engine coolant temperature (ECT) sensor/cylinder head temperature (CHT) sensorout of self-test range | Wiring, cooling system fault, ECT sensor, CHTsensor, ECM |
| P1117 | Engine coolant temperature (ECT) sensor/cylinder head temperature (CHT) sensorcircuit intermittent | Wiring, cooling system fault, ECT sensor, CHT sensor, ECM |
| P1120 | Throttle position (TP) sensor -signal malfunction, low | Wiring, TP sensor |
| P1121 | Throttle position (TP) sensor -inconsistent with mass air flow (MAF) sensor signal | Wiring, MAF sensor, TP sensor, air leak |
| P1124 | Throttle position (TP) sensor -signal malfunction | Mechanical fault, TP sensor, ECM |
| P1125 | Throttle position (TP) sensor -circuit intermittent | Wiring, TP sensor |
| P1127 | Self-test not completed -heated oxygen sensor(H02S), not tested | Engine not running long enough prior to self-test |
| P1156 | Engine control module (ECM)/fuel injector control module -malfunction | Wiring, fuel injector control module, ECM |
| P1157 | Heated oxygen sensor (H02S) 2, bank 2 -not switching, fuel trim (FT) weak mixture | Wiring, exhaust system leaking, H02S |
| P115E | Engine control module (ECM) -data transmissionfault | Throttle position (TP), wiring, ECM |
| P117A | Engine control module (ECM) -engine oiltemperature | Engine overheated, wiring, ECM |
| P1184 | Engine oil temperature (EOT) sensor -out of self-test range | Wiring, EOT sensor, ECM |
| P1227 | Supercharger (SC) wastegate -pressure high | EGR valve, MAF sensor, SC wastegate actuator, SC |
| P1228 | Supercharger (SC) wastegate -pressure low | EGR valve, MAF sensor, SC wastegate actuator,SC |
| P1229 | Charge air cooler (CAC) pump -circuitmalfunction | Wiring, CAC pump relay, CAC pump |
| P1229 | Supercharger (SC) intercooler pump | Wiring, SC intercooler pump, SC intercooler pump relay, ECM |
| P1232 | Low speed fuel pump -malfunction | Wiring, low speed fuel pump relay, ECM |
| P1233 | Fuel system -malfunction | Wiring, IFS switch, fuel pump, fuel pump control module, ECM |
| P1234 | Fuel system -malfunction | Wiring, IFS switch, fuel pump, fuel pump control module, ECM |
| P1235 | Fuel pump control -signal malfunction | Wiring, fuel pump, fuel pump control module, ECM |
| P1236 | Fuel pump control -signal malfunction | Wiring, fuel pump, fuel pump control module, ECM |
| P1237 | Fuel pump -circuit malfunction | Wiring, fuel pump, fuel pump relay, fuel pump control module |
| P1238 | Fuel pump -circuit malfunction | Wiring, fuel pump, fuel pump relay, fuel pump control module |
| P1244 | Alternator -high input | Wiring, alternator, ECM |
| P1245 | Alternator -low input | Wiring, drive belt, alternator, ECM |
| P1246 | Alternator | Wiring, alternator, drive belt, ECM |
| P1260 P1261 | Theft detected -vehicle immobilized Injector circuit, cylinder 1 -high to low side short | -Wiring short circuit |
| P1262 | Injector circuit, cylinder 2 -high to low side short | Wiring short circuit |
| P1263 | Injector circuit, cylinder 3 -high to low side short | Wiring short circuit |
| P1264 | Injector circuit, cylinder 4 -high to low side short | Wiring short circuit |
| P1265 | Injector circuit, cylinder 5 high to low side short | Wiring short circuit |
| P1266 | Injector circuit, cylinder 6 -high to low side short | Wiring short circuit |
| P1267 | Injector circuit, cylinder 7 -high to low side short | Wiring short circuit |
| P1268 P1270 | Injector circuit, cylinder 8 -high to low side short Maximum engine RPM or vehicle speed limit reached | Wiring short circuit Engine over revved in neutral, wheel slippage |
| P1271 | Injector circuit, cylinder 1 -high to low side open | Wiring open circuit |
| P1272 | Injector circuit, cylinder 2 -high to low side open | Wiring open circuit |
| P1273 | Injector circuit, cylinder 3 -high to low side open | Wiring open circuit |
| P1274 | Injector circuit, cylinder 4 -high to low side open | Wiring open circuit |
| P1275 | Injector circuit, cylinder 5 -high to low side open | Wiring open circuit |
| P1276 | Injector circuit, cylinder 6 -high to low side open | Wiring open circuit |
| P1277 | Injector circuit, cylinder 7 -high to low side open | Wiring open circuit |
| P1278 | Injector circuit, cylinder 8 -high to low side open | Wiring open circuit |
| P1285 | Cylinder head temperature (CHT) sensor overheat condition | Wiring, cooling system fault, CHT sensor |
| P1288 | Cylinder head temperature (CHT) sensor -out of self-test range | Wiring, cooling system fault, CHT sensor |
| P1289 | Cylinder head temperature (CHT) sensor high input | Wiring, cooling system fault, CHT sensor |
| P128A | Engine control module (ECM)/cylinder head temperature (CHT) sensor -high input | Wiring, CHT sensor, ECM |
| P1290 | Cylinder head temperature (CHT) sensor -lowinput | Wiring, cooling system fault, CHT sensor |
| P1299 | Cylinder head temperature (CHT) sensor over temperature condition | Wiring, cooling system fault, CHT sensor |
| P1309 | Misfire monitor disabled | CMP sensor, CKP sensor, ECT sensor, MAF sensor, ECM |
| P1336 | Camshaft position (CMP) sensor/crankshaft position (CKP) sensor -signal malfunction | Wiring, CMP sensor, CKP sensor, ECM |
| P1397 | System voltage -out of self-test range | Wiring, battery, alternator |
| P1405 | Exhaust gas recirculation (EGR) system -upstream hose off or plugged | EGR hoses |
| P1406 | Exhaust gas recirculation (EGR) system -downstream hose off or blocked | EGR hoses |
| P1408 | Exhaust gas recirculation (EGR) system -out of self-test range | Wiring, EGR hoses, EGR valve, EGR solenoid,ECM |
| P1409 | Exhaust gas recirculation (EGR) solenoid -circuit malfunction | Wiring, EGR solenoid, ECM |
| P1436 | Ale evaporator temperature sensor -low input | Wiring, AlC evaporator temperature sensor, ECM |
| P1437 | Ale evaporator temperature sensor -high input | Wiring, AlC evaporator temperature sensor, ECM |
| P1443 | Evaporative emission (EVAP) system -malfunction | Wiring, EVAP system hoses, EVAP canister,EVAP canister purge valve |
| P1450 | Evaporative emission (EVAP) system, vent control -circuit malfunction | Wiring, EVAP system hoses, EVAP canister purge valve, fuel filler cap blocked |
| P1451 | Evaporative emission (EVAP) canister purge valve -circuit malfunction | Wiring, EVAP canister purge valve, ECM |
| P145E | Positive crankcase ventilation (PCV) heatercircuit malfunction | Wiring, PCV valve |
| P1460 | Wide open throttle (WOT) relay, AlC -circuit malfunction | Wiring, WOT relay, ECM |
| P1461 | AlC refrigerant pressure sensor -high voltage | Wiring, AlC refrigerant pressure sensor, ECM |
| P1462 | AlC refrigerant pressure sensor -low voltage | Wiring, AlC refrigerant pressure sensor, ECM |
| P1463 | Ale refrigerant pressure sensor -insufficient pressure change | Wiring, AlC system -mechanical fault, AlC refrigerant pressure sensor, AlC compressor clutch |
| P1464 | Ale demand -signal out of self-test range | Wiring, AlC ON -during self-test, WOT relay (AlC cut-out), ECM |
| P1469 | Frequent AlC compressor clutch cycling | Wiring, AlC system -mechanical fault |
| P1474 | Engine coolant blower motor (low speed) control circuit malfunction | Wiring, engine coolant blower motor relay, ECM |
| P1477 | Engine coolant blower motor (medium speed) -control circuit malfunction | Wiring, engine coolant blower motor relay, ECM |
| P1479 | Engine coolant blower motor (high speed) control circuit malfunction | Wiring, engine coolant blower motor relay, ECM |
| P1489 | Crankcase breather heater -circuit malfunction | Wiring, crankcase breather heater |
| P1500 | Vehicle speed sensor (VSS) -circuit intermittent | Wiring, VSS, ECM |
| P1501 | Vehicle speed sensor (VSS) -out of self-test range | Electro-magnetic interference |
| P1502 | Vehicle speed sensor (VSS) -intermittent signal | Wiring, VSS/ABS wheel speed sensors |
| P1504 | Idle air control (lAC) valve -c.ircuit malfunction | Wiring, lAC valve, ECM |
| P1506 | Idle air control (lAC) valve -over-speed error | Wiring, lAC valve, vacuum leaks, ECM |
| P1507 | Idle air control (lAC) valve -under-speed error | Wiring, lAC valve, hose blocked, ECM |
| P1512 | Intake manifold runner control (IMRC) module -malfunction, stuck closed (bank 1) | Wiring, mechanical fault, ECM |
| P1513 | Intake manifold runner control (IMRC) module -malfunction, stuck closed (bank 2) | Wiring, mechanical fault, ECM |
| P1516 | Intake manifold runner control (IMRC) module -input error (bank 1) | Wiring, mechanical fault |
| P1517 | Intake manifold runner control (IMRC) module -input error (bank 2) | Wiring, mechanical fault |
| P1518 | Intake manifold runner control (IMRC) module -malfunction, stuck open | Wiring, IMRC actuator, ECM |
| P1519 | Intake manifold runner control (IMRC) module -malfunction, stuck closed | Wiring, IMRC actuator, ECM |
| P151A | Intake manifold runner control (IMRC) module -malfunction | Wiring, IMRC actuator, ECM |
| P1520 | Intake manifold runner control (IMRC) module -circuit malfunction | Wiring, mechanical fault, vacuum hoses, IMRC actuator, ECM |
| P1537 | Intake manifold runner control (IMRC) module -malfunction, stuck open (bank 1) | Wiring, hoses blocked, mechanical fault, ECM |
| P1538 | Intake manifold runner control (IMRC) module -malfunction, stuck open (bank 2) | Wiring, hoses blocked, mechanical fault, ECM |
| P1549 | Intake manifold air control system -malfunction | Wiring, intake manifold air control solenoid, ECM |
| P1550 | Power steering pressure (PSP) sensor malfunction | Wiring, PSP sensor, ECM |
| P1565 | Cruise control system | Wiring, CPP switch, BPP switch, cruise control module, cruise control master switch, VSS |
| P1566 | Cruise control system | Wiring, CPP switch, BPP switch, cruise control module, cruise control master switch, VSS |
| P1567 | Cruise control system | Wiring, CPP switch, BPP switch, cruise control module, cruise control master switch, VSS |
| P1568 | Cruise control system | Wiring, CPP switch, BPP switch, cruise control module, cruise control master switch, VSS |
| P1572 | Brake pedal position (BPP) switch -circuit intermittent | Wiring, BPP switch, brake fluid pressure (BFP) switch, ECM |
| P1582 | Engine control module (ECM) -throttle data stored | Airbag deployment |
| P1605 | ‘Keep alive’ memory test failure | Wiring, battery terminal corrosion, loose battery connection, ECM |
| P1633 | ‘Keep alive’ power supply -voltage too low | Wiring, ECM |
| P1635 | Tire/axle ratio out of range | Incorrect tire size, incorrect axle ratio, incorrect vehicle 10 configuration |
| P1636 | Engine control module (ECM) -internal fault | ECM |
| P1639 | Engine control module (ECM) -invalid or missing data | Incorrect vehicle 10 configuration, ECM |
| P1640 | Diagnostic trouble codes stored | P-codes stored in another control module |
| P1641 | Fuel pump -circuit malfunction | Wiring, fuel pump relay, fuel pump, ECM |
| P1646 | Engine control module (ECM) -linear oxygen sensor (02S) control, bank 1 | Non OEM accessories, ECM programming, ECM |
| P1647 | Engine control module (ECM) -linear oxygen sensor (02S) control, bank 2 | Non OEM accessories, ECM programming, ECM |
| P1650 | Power steering pressure (PSP) switch -malfunction | Wiring, PSP switch, steering wheel turned during self-test, ECM |
| P1651 | Power steering pressure (PSP) switch -input | Wiring, vehicle towed with engine running, PSP switch, OTC not erased, ECM |
| P1674 | Engine control module (ECM) -malfunction | Wiring, software incompatibility, ECM |
| P1703 | Brake pedal position (BPP) switch -out of self-test range | Wiring, brake pedal depressed during self-test, rear electronic module/lights control module, BPP switch, ECM |
| P1705 | Transmission range (TR) sensor -out of self-test range | Wiring, TR sensor |
| P1709 | Park/neutral position (PNP) switch/clutch pedal position (CPP) switch -out of self-test range | Wiring, PNP switch/CPP switch, ECM |
| P1780 | Overdrive selection switch | Wiring, transmission control switch, ECM |
| P1900 | Output shaft speed (OSS) sensor -circuitintermittent | Wiring, poor connection, OSS sensor, ECMITCM |
| P1901 | Turbine shaft speed (TSS) sensor -circuitintermittent | Wiring, poor connection, TSS sensor, ECMITCM |
| P1910 | Reversing lamps -circuit malfunction | Wiring, reverse gear position switch, ECM |
| U1011 | CAN data bus, air intake -invalid or missing data | Wiring, ECM (alternative fuel), ECM |
| U1020 | CAN data bus, AlC -AlC compressor clutch invalid or missing data | Wiring, AlC trouble code(s) stored |
| U1021 | CAN data bus, AlC -communication error | Wiring, AlC trouble code(s) stored, ECM |
| U1039 | CAN data bus, antilock brake system (ASS) vehicle speed invalid or missing data | Wiring, ABS trouble code(s) stored |
| U1041 | CAN data bus, antilock brake system (ASS) vehicle speed invalid or missing data | Wiring, ABS trouble code(s) stored |
| U1051 | CAN data bus, engine control module (ECM)brake signal invalid or missing data | Wiring, BPP switch, bulb(s) |
| U1071 | CAN data bus, engine sensor data -invalid ormissing data | Wiring, ECM (alternative fuel), ECM |
| U1073 | CAN data bus, cooling system communication error | Wiring, variable load control module, ECM(alternative fuel) -if fitted, ECM |
| U1089 | CAN data bus, active suspension -invalid ormissing data | Wiring, active suspension trouble code(s) stored |
| U1098 | CAN data bus, antilock brake system (ASS)vehicle speed invalid or missing data | Wiring, ABS trouble code(s) stored |
| U1130 | CAN data bus, fuel pump -communication error | Wiring, instrument panel, ECM |
| U1131 | CAN data bus, fuel pump -communication error | Wiring, instrument panel, ECM |
| U1137 | CAN data bus, instrument panel warning devicesinvalid or missing data | Wiring, instrument panel |
| U1147 | CAN data bus, alarm | Wiring, alarm system trouble code(s) stored |
| U1243 | CAN data bus , AlC -invalid or misSing data | Wiring, AlC system trouble code(s) stored |
| U1260 | CAN data bus -communication error | Wiring, ECM (alternative fuel) |
| U1261 | CAN data bus -communication error | Wiring, ECM (alternative fuel) |
| U1262 | CAN data bus -communication error | Wiring, trouble code(s) stored in other control modules |
| U1451 | CAN data bus, alarm | Wiring, alarm system trouble code(s) stored |
| U2015 | Signal link fault | Compuvalve/ECM (alternative fuel) |
| U2195 | CAN data bus, lights control module invalid or missing data | Wiring, lights control module trouble code(s) stored |
