| Scan code | Fault location | Probable cause |
| PO, P2,UO | Refer to OBO-II trouble code tables | – |
| P1110 | Decreased engine performance -high intake airtemperature | Wiring open circuit/short to positive, ground wire defective, IAT sensor, ECT sensor, cooling system, high engine bay temperature, ECM |
| P1192 | Intake air temperature (IAT) sensor -voltage low | Wiring, IAT sensor, ECM |
| P1193 | Intake air temperature (IAT) sensor -voltage high | Wiring, IAT sensor, ECM |
| P1194 | Heated oxygen sensor (H02S), heater control -circuit malfunction | Wiring, H02S, ECM |
| P1195 | Heated oxygen sensor (H02S) 1, bank 1 slow response | Wiring, heating inoperative, exhaust leak, H02S |
| P1196 | Heated oxygen sensor (H02S) 1, bank 2 slowresponse | Wiring, heating inoperative, exhaust leak, H02S |
| P1197 | Heated oxygen sensor (H02S) 2, bank 1 slow response | Wiring, heating inoperative, exhaust leak, H02S |
| P1280 | Fuel pump relay -circuit malfunction | Wiring, fuel pump relay |
| P1281 | Engine temperature -low for long period | Wiring, cooling system, coolant thermostat, ECT sensor |
| P1282 | Fuel pump relay | Wiring open circuit/short circuit, fuel pump relay |
| P1290 | Compressed natural gas pressure sensorpressure high | Compressed natural gas system, wiring,compressed natural gas pressure sensor |
| P1292 | Compressed natural gas pressure sensor voltage high | Wiring, compressed natural gas pressure sensor |
| P1293 | Compressed natural gas pressure sensor voltage low | Wiring, compressed natural gas pressure sensor |
| P1294 | Idle speed control (ISC) system rpm lower/ higher than expected | Wiring, air leak, throttle valve tight/sticking, lAC valve |
| P1295 | Throttle position (TP) sensor -no 5 volt supply | Wiring, TP sensor, ECM |
| P1296 | Manifold absolute pressure (MAP) sensor no 5 volt supply | Wiring, MAP sensor, ECM |
| P1297 | Manifold absolute pressure (MAP) sensor | Wiring, hose connection(s), MAP sensor |
| P1298 | System too lean -at prolonged wide open throttle | Intake/exhaust leak, MAP sensor, fuel pressure/pump, injector(s), H02S |
| P1299 | Manifold absolute pressure (MAP) sensor/ throttle position (TP) sensor | Intake leak, hose connection(s), MAP sensor, TP sensor |
| P1388 | Engine control relay | Wiring open circuit/short circuit, engine control relay |
| P1389 | Engine control relay | Wiring open circuit, engine control relay |
| P1391 | Crankshaft position (CKP) sensor/camshaft position (CMP) sensor -intermittent signal | Wiring, poor connection, air gap, CKP sensor, CMP sensor |
| P1398 | Engine control module (ECM) -misfire detection limit reached | Wiring, poor connection, CKP sensor |
| P1475 | Engine control module (EeM) -auxiliary 5 volt output high | Wiring, ECM |
| P1476 | Secondary air injection (AIR) system -insufficientflow detected | AIR pump, AIR valve, AIR hose(s) |
| P1477 | Secondary air injection (AIR) system excessive flow detected | AIR pump, AIR valve, AIR hose(s), ECM |
| P1478 | Ambient/battery temperature sensor -range! performance problem | Wiring, ambient/battery temperature sensor |
| P1479 | Transmission cooling fan relay -circuit malfunction | Wiring, transmission fluid level low, transmission cooling fan, transmission cooling fan relay |
| P1486 | Evaporative emission (EVAP) system blockage detected | Hose connection(s), hose blocked/trapped, EVAP canister |
| P1488 | Engine control module (ECM) -auxiliary 5 volt output low | Wiring, ECM |
| P1491 | Engine coolant blower motor relay -circuit malfunction | Wiring open circuit/short circuit, engine coolant blower motor |
| P1492 | Ambient/battery temperature sensor -voltage high | Wiring, ambient/battery temperature sensor |
| P1493 | Ambient/battery temperature sensor -voltage low | Wiring, ambient/battery temperature sensor |
| P1494 | Evaporative emission (EVAP) leak detection pump pressure switch | Wiring, hose leak/blockage, EVAP leak detection pump |
| P1495 | Evaporative emission (EVAP) leak detection pump solenoid | Wiring open circuit/short circuit, hose leak! blockage, EVAP leak detection pump solenoid |
| P1496 | Engine control module (ECM) -5 volt output low | ECM |
| P1594 | Alternator -voltage high | Wiring, battery, alternator |
| P1595 | Cruise control | Wiring open circuit/short circuit, hoses, cruise control master switch, cruise control vacuum switching valve |
| P1596 | Cruise control master switch -high voltage | Wiring, cruise control master switch |
| P1597 | Cruise control master switch -low voltage | Wiring, cruise control master switch |
| P1598 | NC refrigerant pressure sensor -high input | Wiring, AlC refrigerant pressure too high (cooling fault/incorrectly charged), AlC refrigerant pressure sensor |
| P1599 | AlC refrigerant pressure sensor -low input | Wiring, AlC refrigerant pressure too low (incorrectly charged), AlC refrigerant pressure sensor |
| P1602 | Engine control module (ECM) not programmed | New ECM not programmed, incorrectly programmed, ECM |
| P1680 | Clutch pedal position (CPP) switch -circuit malfunction | Wiring, CPP switch, ECM |
| P1682 | Alternator -voltage low | Wiring, battery, alternator drive belt, alternator |
| P1683 | Cruise control | Wiring, cruise control vacuum switching valve |
| P1684 | Engine control module (ECM) -supply voltagedisconnected within last 50 ignition switch ON-OFF cycles | Wiring, battery |
| P1685 | Key not programmed into immobilizer control module | Wiring, ignition key not matchedldamaged,immobilizer control module |
| P1686 | CAN data bus, immobilizer control module no signal | Wiring, immobilizer control module |
| P1687 | CAN data bus, instrumentation -no signal | Wiring, instrumentation control module(mechanical) |
| P1693 | Engine control module (ECM) | Companion module trouble code detected in ECM |
| P1694 | CAN data bus, engine control m.odule (ECM) nosignal | Wiring, ECM |
| P1696 | Engine control module (ECM) -EEPROM error | ECM |
| P1698 | CAN data bus, transmission control module (TCM) no signal | Wiring, TCM |
| P1719 | Skip shift solenoid -circuit malfunction | Wiring open circuitlshort circuit, skip shift solenoid |
| P1740 | Torque converter clutch (TCC)/overdrive solenoid-performance problem | TCC, overdrive solenoid, transmission mechanical fault |
| P17S6 | Governor pressure not equal to target (15-20PSI) -mid pressure malfunction | Signal wire open circuitlshort circuit, valve body, sensor supply wire open circuit, transmission fluid level, governor pressure solenoid, transmission mechanical fault, ECMITCM -no 5 volt supply |
| P1757 | Governor pressure not equal to target zeropressure malfunction | Signal wire open circuitlshort circuit, valve body, sensor supply wire open circuit, transmission fluid level, governor pressure solenoid, transmission mechanical fault, ECMfTCM -no S volt supply |
| P1762 | Governor pressure sensor -incorrect signal | Signal wire short circuit to ground/positive, supply wire open circuitlshort circuit, transmission fluid level, governor pressure solenoid, governor pressure sensor, ECMITCM |
| P1763 | Governor pressure sensor -signal high | Signal wire short circuit to positive, supply wire open circuit, transmission fluid level, governor pressure sensor, ECMfTCM |
| P1764 | Governor pressure sensor -signal low | Signal wire short circuit to ground, supply wire open circuit, transmission fluid level, governor pressure sensor, ECMITCM |
| P176S | Transmission system relay | Wiring open circuitlshort circuit, transmission system relay, ECMfTCM |
| P1899 | Park/neutral position (PNP) switch -input circuitmalfunction | Wiring, PNP switch, ECMITCM |
