Powertrain Codes (P-Codes): Full List
Powertrain codes start with P and cover the engine, fuel and ignition systems, emission controls and the transmission. They are the codes that most often turn on the check engine light and the ones most relevant to a smog check or emissions test. The third character narrows it down: 1–2 fuel and air metering, 3 ignition and misfire, 4 emission controls, 5 speed and idle, 6 computer and outputs, 7–9 transmission, A hybrid.
539Codes
2.7Average severity
12%High or critical
20%DIY-friendly
Severity distribution
Most viewed
P0135
Powertrain
The heater inside the upstream oxygen sensor on bank 1 isn't working or its circuit is faulty.
Low
P0174
Powertrain
The cylinder bank without cylinder 1 is running lean even with the maximum fuel correction…
Moderate
P0113
Powertrain
The intake air temperature signal is stuck at maximum voltage, which usually means an open…
Low
P0171
Powertrain
The engine computer is adding the maximum extra fuel it's allowed on bank 1 and still sees…
Moderate
P0172
Powertrain
The engine computer is pulling as much fuel as it's allowed on bank 1 and the mixture is still…
Moderate
P0299
Powertrain
The turbo or supercharger isn't building the boost pressure the engine computer is asking for.
Moderate
All codes (318)
P0884
Powertrain
The transmission computer's power supply dropped out briefly – usually a battery, ground…
Moderate
P0887
Powertrain
The circuit that switches the transmission power relay reads high voltage when it shouldn't.
Moderate
P0894
Powertrain
The transmission computer measured slip inside the gearbox that shouldn't be there. Clutches…
High
P090C
Ford · Powertrain
The PowerShift TCM sees a low signal on the motor that works clutch B, the even-gear…
Moderate
P0A0F
Powertrain
The hybrid system spun the gas engine with its motor-generator to start it, but the engine…
High
P0A1F
Powertrain
The module that manages the high-voltage battery failed its self-check or reports implausible…
Moderate
P0A7E
Powertrain
The high-voltage battery got too hot. A clogged cooling intake or dirty fan is the usual cause.
Moderate
P0A7F
Powertrain
The battery computer has calculated that the whole high-voltage pack has worn past its usable…
Moderate
P0A80
Powertrain
The hybrid system sees weak or unbalanced modules in the high-voltage battery and flags…
Moderate
P0A93
Powertrain
The inverter's separate coolant loop isn't carrying heat away – usually a dead electric…
High
P0A94
Powertrain
A hybrid voltage converter isn't delivering the voltage it should – on Toyotas, the boost…
High
P0A95
Powertrain
The main fuse in the high-voltage battery circuit has opened or its circuit reads open…
Critical
P0AA6
Powertrain
High voltage is leaking toward the car body somewhere – an insulation fault that must be found…
High
P0AFA
Powertrain
Total high-voltage battery voltage dropped below the minimum the system allows, so power…
High
P1128
Volkswagen · Powertrain
VW's part-load fuel adaptation has maxed out adding fuel on bank 1 – the engine runs lean as…
Moderate
P1217
Nissan · Powertrain
Nissan's ECM saw engine coolant get hotter than it should, usually because the radiator fan…
Critical
P1233
Ford · Powertrain
The Ford PCM lost the status signal from the fuel pump driver module, so fuel pump control…
Moderate
P1259
Honda · Powertrain
The PCM saw the VTEC solenoid or VTEC oil pressure switch misbehave on an older Honda VTEC…
Moderate
P1260
Ford · Powertrain
Ford's Passive Anti-Theft System didn't accept the key, so the PCM shut off fuel and the engine…
Moderate
P1272
Nissan · Powertrain
The front air/fuel ratio sensor on bank 1 isn't sending a usable, moving signal to the Nissan…
Moderate
P1285
Ford · Powertrain
Ford's cylinder head temperature sensor reports the engine is overheating. Pull over and shut…
Critical
P1289
Ford · Powertrain
The CHT sensor signal on your Ford is stuck near 5 volts, which the PCM reads as an impossibly…
Moderate
P1295
Hyundai · Powertrain
Hyundai's engine computer no longer trusts the electronic throttle and has cut power as…
High
P1297
Volkswagen · Powertrain
Boost is escaping between turbo and throttle body – usually a split hose or a leaking diverter…
Moderate
P1299
Ford · Powertrain
The engine got so hot that the Ford PCM is shutting off fuel to cylinders to save it. Stop…
Critical
P1300
Toyota · Powertrain
Toyota's ECM fires ignition coil No. 1 but gets no confirmation pulse (IGF) back from its…
Moderate
P1305
Toyota · Powertrain
The igniter in Toyota coil No. 2 stops confirming its sparks, often only once the engine is hot.
Moderate
P1310
Toyota · Powertrain
No spark confirmation from one Toyota coil: No. 3 on four-cylinders, but a different coil…
Moderate
P1320
Nissan · Powertrain
The Nissan ECM isn't seeing the ignition primary signal it expects while the engine cranks…
Moderate
P1326
Hyundai · Powertrain
Hyundai's KSDS software heard vibration typical of worn rod bearings and put the engine in limp…
Critical