| OBD·II code | Fault location | Probable cause |
| PO,P2, UO | Refer to OBD-11 trouble code tables | – |
| P1106 | Manifold absolute pressure (MAP) sensor – circuit/intermittent voltage high | Wiring, MAP sensor |
| P1107 | Manifold absolute pressure (MAP) sensor – circuit/ intermittent voltage low | Wiring, MAP sensor |
| P1111 | Intake air temperature (IAT) sensor- circuit/
intermittent voltage high | Wiring, IAT sensor |
| P1112 | Intake air temperature (IAT) sensor- circuit!
intermittent voltage low | Wiring, IAT sensor |
| P1114 | Engine coolant temperature (ECT) sensor – circuit/intermittent voltage low | Wiring, ECT sensor |
| P1115 | Engine coolant temperature (ECT) sensor – circuit/intermittent voltage high | Wiring, ECT sensor |
| P1120 | Throttle motor position sensor 1 – circuit malfunction | Wiring open circuit/short circuit to ground/ short circuit to positive, throttle control unit, ECM |
| P1121 | Throttle position (TP) sensor- circuit!
intermittent voltage high | Wiring, TP sensor |
| P1122 | Throttle position (TP) sensor- circuit!
intermittent voltage low | Wiring, TP sensor |
| P1125 | Throttle position (TP) motor- fail safe mode | Wiring, TP sensor, TP motor, mechanical fault, ECM |
| P1133 | Heated oxygen sensor (H02S) – RH front- insufficient switching | Exhaust system, wiring, H02S, ECM |
| P1134 | Heated oxygen sensor (H02S) – RH front – slow operation | Exhaust system, wiring, H02S, ECM |
| P1153 | Heated oxygen sensor (H02S) – LH front – insufficient switching | Exhaust system, wiring, H02S, ECM |
| P1154 | Heated oxygen sensor (H02S) – LH front – slow operation | Exhaust system, wiring, H02S, ECM |
| P1167 | Fuel trim, bank 1 – mixture too rich during deceleration | Injectors, fuel pump, fuel pressure, ECM |
| P1169 | Fuel trim, bank 2 – mixture too rich during deceleration | Injectors, fuel pump, fuel pressure, ECM |
| P1171 | Fuel system – mixture lean under acceleration | Fuel pump/strainer, incorrect fuel |
| P1220 | Throttle motor position sensor 2 – circuit malfunction | Wiring open circuit/short circuit to ground/ short circuit to positive, throttle control unit, ECM |
| P1221 | Throttle motor position sensor 1/2- signal variation | Wiring, throttle control unit, ECM |
| P1271 | Accelerator pedal position (APP) sensor 1/2- signal variation | Wiring, APP sensor, ECM |
| P1272 | Accelerator pedal position (APP) sensor 2/3 – signal variation | Wiring, APP sensor, ECM |
| P1273 | Accelerator pedal position (APP) sensor 1/3- signal variation | Wiring, APP sensor, ECM |
| P1275 | Accelerator pedal position (APP) sensor 1 – circuit malfunction | Wiring open circuit/short circuit to ground/
short circuit to positive, APP sensor, ECM |
| P1280 | Accelerator pedal position (APP) sensor 2 – circuit malfunction | Wiring open circuit/short circuit to ground/
short circuit to positive, APP sensor, ECM |
| P1285 | Accelerator pedal position (APP) sensor 3 – circuit malfunction | Wiring, APP sensor, ECM· |
| P1290 | Throttle position (TP) motor -forced idle mode | Wiring, APP sensor, TP motor, mechanical fault, ECM |
| P1295 | Throttle position (TP) motor – power management mode | Wiring, TP sensor, TP motor, MAP sensor, MAF sensor, ECM |
| P1299 | Throttle position (TP) motor – forced engine shut down mode | Wiring, TP sensor, TP motor, MAP sensor, MAF sensor, ECM |
| P1310 | Ignition control module (ICM) – diagnosis | Wiring, ignition coil(s), ICM, ECM |
| P1311 | Ignition control module (ICM) – ignition·coil secondary coil signal, circuit 1
| Wiring, ignition coil(s), ICM, ECM |
| P1312 | Ignition control module (ICM) – ignition coil secondary coil signal, circuit 2 | Wiring, ignition coil{s), ICM, ECM |
| P1326 | Ignition control module (ICM) – combustion quality input signal | Wiring, ignition coil(s), ICM, ECM |
| P1340 | Ignition control module (ICM) – cylinder identification/syncronization | Wiring, ignition coil(s), ICM, ECM |
| P1380 | Engine control module (ECM)/ABS control module, rough road signal – communication fault | Wiring, ABS trouble code(s) stored, ECM |
| P1381 | Engine control module (ECM)/ABS control module – communication fault | Wiring, ABS trouble code(s) stored, ECM |
| P1390 | G-force sensor – intermittent voltage low | Wiring, G-force sensor |
| P1391 | G-force sensor – performance | Seal damaged/missing, incorrectly installed, wiring, G-force sensor, ECM |
| P1392 | G-force sensor – voltage low | Wiring, G-force sensor, ECM |
| P1393 | G-force sensor – voltage high | Wiring, G-force sensor, ECM |
| P1394 | G-force sensor – intermittent voltage high | Wiring, G-force sensor |
| P1404 | Exhaust gas recirculation (EGR) valve – valve closed | Wiring, EGR valve |
| P1406 | Exhaust gas recirculation (EGR) valve position sensor – circuit problem | Wiring, EGR valve/position sensor, ECM |
| P1441 | Evaporative emission (EVAP) canister purge system – flow detected | Wiring, EVAP solenoid, ECM |
| P1508 | Idle air control (lAC) system – low RPM | Intake system, throttle body, hose leak, wiring, lAC valve, ECM |
| P1509 | Idle air control (lAC) system – high RPM | Hose leak, throttle body, crankcase vent valve, wiring, lAC valve, ECM |
| P1514 | Throttle position (TP) sensor/mass air flow
(MAF) sensor – signal variation | Wiring, TP sensor, MAP sensor, ECM |
| P1515 | Throttle command/actual throttle position – signal variation | Wiring, throttle valve sticking, throttle control unit, ECM |
| P1516 | Throttle position motor – position performance | Throttle valve tight/sticking, TP sensor, wiring, throttle control unit, ECM |
| P1523 | Throttle position motor – closed position performance | Throttle valve tight/sticking, TP sensor, wiring open circuit/short circuit to ground, throttle control unit, ECM |
| P1571 | Brake pedal position (BPP) switch – no operation | Wiring, BPP switch |
| P1618 | Engine control module (ECM) – internal fault | ECM |
| P1625 | Engine control module (ECM) – unexpected reset | Interference from non standard electronics, erase trouble code and re-test |
| P1635 | Sensor supply voltage – circuit 1 malfunction | Wiring short circuit to ground/positive, ground wiring open circuit, ECM |
| P1639 | Sensor supply voltage – circuit 2 malfunction | Wiring short circuit to ground/positive, ground wiring open circuit, throttle position (TP) sensor, ECM |
| P1640 | Engine control module (ECM), output driver – internal fault | Wiring, ECM |
| P1646 | Sensor supply voltage – circuit C malfunction | Wiring short circuit to ground/positive, ground wiring open circuit, accelerator pedal position (APP) sensor, ECM |
| P1650 | Engine control module quad driver/output driver | Wiring, evaporative emission (EVAP) canister purge valve, intake manifold air control solenoid, ECM |
| P1790 | Engine control module (ECM) – AT ROM
checksum error | ECM/programming |
| P1792 | AT -AT EEPROM checksum error | ECM/programming |
| P1835 | AT – kick-down switch | Wiring, kick-down switch, ECM |
| P1850 | AT – brake band solenoid malfunction | AT trouble code(s) stored |
| P1860 | AT- torque converter clutch (TCC) solenoid circuit | Wiring, TCC solenoid, ECM |
| P1870 | AT – component slipping | Range switch, mechanical failure, engine speed signal incorrect |