| Scan code | Fault location | Probable cause |
| PO, P2, UO | Refer to OBO-II trouble code tables | – |
| P1031 | Heated oxygen sensor (H02S) 1, bank 1 heatercurrent monitor control circuit | Wiring short circuit to positive, H02S, ECM |
| P1032 | Heated oxygen sensor (H02S) 1, bank 1 heaterwarm up control circuit | Wiring short circuit to positive, H02S, ECM |
| P1106 | Manifold absolute pressure (MAP) sensor circuit intermittent voltage high | Wiring open circuit/short circuit to ground/ short circuit to positive |
| P1107 | Manifold absolute pressure (MAP) sensor circuit intermittent -voltage low | Wiring short circuit to ground |
| P1108 | Barometric pressure (BARO) sensor/manifoldabsolute pressure (MAP) sensor -comparison too high | Wiring open circuit/short circuit to positive, MAP sensor, ECM |
| P1111 | Intake air temperature (IAT) sensor -circuitintermittent -voltage high | Wiring open circuit, ground lead defective |
| P1112 | Intake air temperature (lAT) sensor -circuit intermittent -voltage low | Wiring short circuit to ground |
| P1114 | Engine coolant temperature (ECT) sensor circuit malfunction -voltage low | Wiring short circuit to ground |
| P1115 | Engine coolant temperature (ECT) sensor circuit malfunction -voltage high | Wiring open circuit, ground lead defective |
| P1121 | Throttle position (TP) sensor -circuit malfunction -voltage high | Wiring short circuit to positive, ground lead defective |
| P1122 | Throttle position (TP) sensor -circuit malfunction -voltage low | Wiring open circuit/short circuit to ground |
| P1133 | Heated oxygen sensor (H02S) 1, bank 1insufficient switching | Wiring, oxygen sensor heater, exhaust system leaking, H02S |
| P1134 | Heated oxygen sensor (H02S) 1, bank 1 slow response | Wiring, oxygen sensor heater, exhaust system leaking, H02S |
| P1139 | Heated oxygen sensor (H02S) 2, bank 1insufficient switching | Wiring, oxygen sensor heater, exhaust system leaking, H02S |
| P1140 | Heated oxygen sensor (H02S) 2, bank 1 slow response | Wiring, oxygen sensor heater, exhaust system leaking, H02S |
| P1153 | Heated oxygen sensor (H02S) 1, bank 2insufficient switching | Wiring, oxygen sensor heater, exhaust system leaking, H02S |
| P1154 | Heated oxygen sensor (H02S) 1, bank 2 slow response | Wiring, oxygen sensor heater, exhaust system leaking, H02S |
| P1258 | Engine overheating | Cooling system, engine coolant temperature (ECT) sensor |
| P1320 | Ignition control module (ICM) -4X reference circuit, intermittent | Wiring open circuit/short circuit to ground, ICM, ECM |
| P1323 | Ignition control module (ICM) -24X reference circuit, low frequency | Wiring open circuit/short circuit to ground, ICM,ECM |
| P1336 | Crankshaft, position (CKP) sensor -variation not leamed | Learning procedure not performed |
| P1350 | Ignition control module (ICM) -bypass line monitor circuit malfunction | Wiring open circuit/short circuit to groundl short circuit to positive, ICM, ECM |
| P1359 | Ignition control module (ICM) bank 1 -circuit malfunction | Wiring open circuit/short circuit to positive, ICM, ECM |
| P1360 | Ignition control module (lCM) bank 2 -circuit malfunction | Wiring open circuit/short circuit to positive, ICM, ECM |
| P1370 | Ignition control module (ICM) -4X reference circuit, too many pulses | Wiring, electromagnetic interference, ICM |
| P1371 | Ignition control module (ICM) -4X reference circuit, too few pulses | Wiring, electromagnetic interference, ICM |
| P1372 | Crankshaft position (CKP) sensor | Wiring open circuit/short circuit to ground/short circuit to positive, CKP sensor, ECM |
| P1375 | Ignition control module (ICM) -24X referencecircuit, voltage high | Wiring open circuit/short circuit to ground/short circuit to positive, CKP sensor(s), ICM |
| . P1376 | Ignition control module (ICM) -ground circuit | Wiring open circuit/short circuit to positive, ground lead defective, ICM |
| P1377 | Ignition control module (ICM) -cam pulse/4Xreference pulse | Wiring open circuit/short circuit to ground, electromagnetic interference, valve timing |
| P1380 | Rough road signal -signal error | ABS control module trouble code(s) stored |
| P1381 | Rough road signal -no communication from ASS CAN data bus . | Wiring open circuit, ABS system |
| P1404 | Exhaust gas recirculation (EGR) valve -stuck open | Wiring open circuit/short circuit to positive, exhaust gas recirculation (EGR) valve position sensor, EGR solenoid |
| P1406 | Exhaust gas recirculation (EGR) valve position sensor circuit malfunction | Wiring open circuit/short circuit to ground/ short circuit to positive, exhaust gas recirculation (EGR) valve position sensor, EGR valve |
| P1415 | Secondary air injection (AIR) system | Wiring, hoses blockedlleaking, AIR valve |
| P1416 | Secondary air injection (AIR) system | Wiring, hoses blockedlleaking, AIR valve, AIR pump relay |
| P1441 | Evaporative emission (EVAP) system -leak detected | Hose connection(s), EVAP canister, EVAP canister purge valve |
| P1483 | Engine cooling system -performance | Cooling system, engine coolant temperature (ECT) sensor, intake air temperature (IAT) sensor |
| P1508 | Idle air control (lAC) valve -rpm low | Wiring open circuit/short circuit to ground, intake system blocked, throttle valve, lAC valve, ECM |
| P1509 | Idle air control (lAC) valve -rpm high | Wiring open circuit/short circuit to ground, intake system blocked, throttle valve, lAC valve, ECM |
| P1520 | Park/neutral position (PNP) switch | Wiring short circuit to ground, incorrectly adjusted |
| P1524 | Throttle position (TP) sensor -learned closed throttle angle | Accelerator cable adjustment, throttle valve tight/sticking, throttle valve incorrectly adjusted |
| P1526 | Minimum throttle position not learned | Initial learn procedure not carried out |
| P1533 | A/C refrigerant temperature sensor -circuit ·malfunction low pressure side | Wiring open circuit/short circuit to ground, A/C refrigerant temperature sensor, ECM |
| P1535 | A/C refrigerant temperature sensor -circuit malfunction high pressure side | Wiring open circuit/short circuit to ground, A/C refrigerant temperature sensor, ECM |
| P1536 | A/C system -ECT over temperature | Cooling system |
| P1537 | A/C request circuit -voltage low | Wiring open circuit/short circuit to ground, A/C refrigerant low pressure switch, A/C control module, ECM |
| P1538 | A/C request circuit -voltage high | Wiring open circuit/short circuit to positive, A/C control module, ECM |
| P1540 | A/C system -high pressure | Wiring open circuit, A/C refrigerant high pressure switch, A/C system, ECM |
| P1542 | A/C system -high pressure/high temperature | High ambient temperature, A/C cooling system |
| P1545 | Ale compressor clutch relay -circuit malfunction | Wiring open circuit/short circuit to ground, supply wire, Ale compressor clutch relay, ECM |
| P1554 | Cruise control status circuit -high voltage | Wiring open circuit/short circuit to ground, cruise control module, ECM |
| P1560 | Cruise control -transmission not in drive | Driver error, transmission fluid pressure (TFP) switch circuit |
| P1564 | Cruise control -acceleration too high | Slippery road conditions |
| P1566 | Cruise control -engine speed too high | Slippery road conditions, transmission mechanical fault |
| P1567 | Cruise control -active brake control system active | Active brake control system engaged with cruise control on |
| P1570 | Cruise control -traction control system (TCS) active | Slippery road surface |
| P1571 | Traction control system (TCS), torque request circuit | Wiring open circuit/short circuit to ground/short circuit to positive, ABS control module trouble code(s) stored, ECM |
| P1574 | Brake pedal position (BPP) switch -voltage high | Wiring, ABS |
| P1575 | Brake pedal position (BPP) switch -extended travel contacts -voltage high | Wiring, ABS |
| P1579 | Transmission shifted from PIN to O/R at high throttle angle | Driver error, wiring, transmission range (TR) switch |
| P1585 | Cruise control system -inhibit output circuit | Wiring open circuit/short circuit to ground/short circuit to positive, supply wire, cruise control motor/actuator, ECM |
| P1599 | Engine stall or near stall detected | ECM trouble code(s) stored, mechanical fault, transmission mechanical fault |
| P1602 | CAN data bus -antilock brake system (ABS)/ traction control system (TCS) | Wiring, ABS control module trouble code(s) stored |
| P1603 | CAN data bus -sensing/diagnostic module (SOM) | Wiring |
| P1604 | CAN data bus -instrument panel | Wiring, body control module (SCM) trouble code(s) stored |
| P1605 | CAN data bus -A/C | Wiring, A/C system trouble code(s) stored |
| P1617 | Engine oil level switch -circuit malfunction | Wiring short circuit to ground, engine oil level, ECM |
| P1621 | Engine control module (ECM) -memoryperformance | ECM |
| P1624 | Customer snapshot function operated | ECM trouble codes stored |
| P1626 | CAN data bus, immobilizer | Wiring, body control module (SCM) trouble code(s) stored |
| P1630 | Engine control module (ECM), immobilizer codeleaming mode | Immobilizer code not programmed |
| P1631 | Engine control module (ECM) -incorrect immobilizer code | Incorrect key, immobilizer code not programmed |
| P1633 | Engine control module (ECM) ignition supply voltage, voltage low | Wiring open circuit, ECM |
| P1634 | Engine control module (ECM) -ignition supply voltage -voltage low | Wiring open circuit, ECM |
| P1635 | Sensor supply voltage -circuit A malfunction | Wiring short circuit to ground/positive, ground wiring open circuit, TP sensor, MAP sensor, EGR valve position sensor, ECM |
| P1637 | Alternator ‘L’ terminal -circuit malfunction | Wiring open circuit/short circuit to ground, alternator, battery temperature sensor, ECM |
| P1638 | Alternator ‘F’ terminal -circuit malfunction | Wiring open circuit/short circuit to ground, alternator, ECM |
| P1639 | Sensor supply voltage -circuit B malfunction | Wiring short circuit to ground/positive, ground wiring open circuit, A/C refrigerant pressure sensor, fuel tank pressure (FTP) sensor, ECM |
| P1640 | Engine control module (ECM) quad driverl output driver | Wiring, ECM controlled components, ECM 0 |
| P1641 | Malfunction indicator lamp (MIL) -circuit malfunction | Wiring open circuit/short circuit to ground, MIL, supply wire, ECM |
| P1642 | Vehicle speed sensor (VSS) -circuit malfunction | Wiring open circuit/short circuit to groundl short circuit to positive, VSS, ECM |
| P1644 | Delivered torque -circuit malfunction | Wiring open circuit/short circuit to ground/short circuit to positive, ASS trouble codes stored, ECM |
| P1645 | Evaporative emission (EVAP) solenoid circuit malfunction | Wiring open circuit/short circuit to ground, EVAP solenoid, ECM |
| P1646 | Evaporative emission (EVAP) canister purge valve -circuit malfunction | Wiring open circuit/short circuit to ground, EVAP canister purge valve, ECM |
| P1650 | Engine control module (ECM) quad driver! output driver | Wiring, ECM controlled components, ECM 0 |
| P1653 | A/C compressor clutch relay -circuit malfunction | Wiring open ‘circuit/short circuit to ground, supply wire, A/C compressor clutch relay, ECM |
| P1654 | Cruise control disable circuit -circuit malfunction | Wiring open circuit/short circuit to groundl short circuit to positive, cruise control module, ECM |
| P1660 | Engine coolant blower motor relay(s) -circuit malfunction | Wiring open circuit/short circuit to ground, engine coolant blower motor relay(s), ECM |
| P1689 | Traction control system (TC8) -delivered torque output circuit | Wiring open circuit/short circuit to groundl short circuit to positive, ABS trouble codes stored, ECM |
