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
P0174
Powertrain
The cylinder bank without cylinder 1 is running lean even with the maximum fuel correction…
Moderate
P0420
Powertrain
The bank 1 catalytic converter no longer stores enough oxygen to clean the exhaust properly.
Low
P0101
Powertrain
The MAF sensor's airflow reading doesn't match what the engine computer expects…
Low
P0113
Powertrain
The intake air temperature signal is stuck at maximum voltage, which usually means an open…
Low
P0135
Powertrain
The heater inside the upstream oxygen sensor on bank 1 isn't working or its circuit is faulty.
Low
P0171
Powertrain
The engine computer is adding the maximum extra fuel it's allowed on bank 1 and still sees…
Moderate
All codes (539)
P1690
Hyundai · Powertrain
The engine computer asked the SMARTRA immobilizer unit to check your key and got no answer back.
Moderate
P1693
Kia · Powertrain
The immobilizer couldn't read a valid code from the chip in your Kia key, so the engine isn't…
Moderate
P1698
Jeep · Powertrain
The engine computer stopped hearing from the transmission computer, often leaving the Jeep…
Moderate
P1702
Ford · Powertrain
Ford's gear selector position signal drops out now and then, so the PCM briefly loses track…
Moderate
P1735
Volkswagen · Powertrain
The DSG control unit lost a valid signal from the sensor that tracks clutch 1 and locks out…
High
P175D
Volkswagen · Powertrain
The DSG computer saw clutch 1 let go while it was supposed to stay engaged, so it cut…
High
P1778
Nissan · Powertrain
The Jatco CVT's step motor is being commanded, but the pulley ratio isn't following it as it…
High
P17F0
Nissan · Powertrain
The TCM detected judder it blames on the CVT itself, usually belt or pulley slip inside…
High
P17F1
Nissan · Powertrain
The TCM caught a judder event it links to the CVT's control valve (valve body), not yet to belt…
Moderate
P1E00
Chevrolet · Powertrain
Volt/Bolt pointer code: the hybrid/EV controller found a fault and asked for the check engine…
Moderate
P2002
Powertrain
The ECU thinks the diesel particulate filter isn't trapping soot properly — or it can't measure…
Moderate
P2004
Powertrain
The intake runner or tumble flaps stay open when told to close, usually a vacuum or linkage…
Low
P2006
Powertrain
The intake swirl or runner flaps stay shut when the ECU wants them open, choking airflow…
Moderate
P2009
Powertrain
The runner or tumble flap solenoid circuit reads too low: a short to ground, an open coil…
Low
P200A
Powertrain
The ECU switched the intake runner flaps but the system didn't respond the way it should.
Low
P2015
Powertrain
The sensor on the intake manifold flaps reports a position that doesn't match what the ECU…
Low
P204F
Powertrain
The DEF/SCR system isn't cutting NOx the way it should; ignored, it leads to a severe speed…
Moderate
P207F
Powertrain
The ECM thinks the DEF in the tank is too weak or contaminated, often right after a refill.
Moderate
P2096
Powertrain
The sensor behind the catalytic converter keeps reporting lean, and the ECU has run out of room…
Low
P2097
Powertrain
The sensor behind the converter keeps seeing rich exhaust, and the ECU can't lean the mixture…
Low
P20E8
Powertrain
The DEF pump can't build or hold enough pressure; suspect a leak, frozen line, clogged filter…
Moderate
P20EE
Powertrain
The SCR catalyst isn't removing enough NOx; DEF quality, dosing, a NOx sensor or the catalyst…
Moderate
P2100
Powertrain
The computer can't push current through the throttle motor – the circuit to the throttle body…
High
P2101
Powertrain
The throttle plate isn't reaching the position the computer asks for, fast enough or accurately…
Moderate
P2102
Powertrain
Too little current or voltage reaches the throttle motor – usually resistance in the feed, not…
Moderate
P2103
Powertrain
The throttle motor circuit draws too much current – a short, a shorted motor or a plate that…
Moderate
P2104
Powertrain
A fail-safe has locked the engine at idle and the gas pedal no longer works – another code…
High
P2105
Powertrain
The engine computer shut the engine off on purpose because it could no longer control…
Critical
P2106
Powertrain
Reduced-power limp mode: the PCM caught a throttle or pedal fault – look for the companion code.
Moderate
P2107
Powertrain
The processor supervising the electronic throttle failed its self-check – a computer fault, not…
High