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
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
P0172
Powertrain
The engine computer is pulling as much fuel as it's allowed on bank 1 and the mixture is still…
Moderate
All codes (539)
P0000
Powertrain
P0000 is not a fault: the scanner found no stored code. It is a placeholder that means…
Minor
P0001
Powertrain
The PCM can't drive the solenoid that meters fuel into the high-pressure pump. Often a no-start…
High
P0008
Powertrain
Camshaft timing on bank 1 has drifted from the crankshaft. Often a stretched timing chain.
Moderate
P0010
Powertrain
The PCM found an electrical fault in the intake cam phaser solenoid circuit on bank 1, not…
Low
P0011
Powertrain
The bank 1 intake cam sits further advanced than the PCM asked for, usually an oil or control…
Moderate
P0012
Powertrain
The bank 1 intake cam lags behind the angle the PCM wants, often from chain stretch or weak oil…
Moderate
P0013
Powertrain
Electrical fault in the bank 1 exhaust cam phaser solenoid circuit; the exhaust cam stays…
Low
P0014
Powertrain
The bank 1 exhaust cam won't follow its target and stays too far advanced; think oil, valve…
Moderate
P0015
Powertrain
The bank 1 exhaust cam sits later than commanded; a stretched chain or stuck exhaust phaser…
Moderate
P0016
Powertrain
The bank 1 intake cam and the crankshaft are out of step, most often from a stretched or jumped…
High
P0017
Powertrain
The bank 1 exhaust cam signal doesn't line up with the crankshaft; think chain, exhaust phaser…
Moderate
P0018
Powertrain
The bank 2 intake cam is out of step with the crankshaft on a V or boxer engine; chain wear…
High
P0019
Powertrain
The bank 2 exhaust cam signal doesn't match the crankshaft; chain, bank 2 exhaust phaser…
Moderate
P0020
Powertrain
Electrical fault in the bank 2 intake cam solenoid circuit on a V or boxer engine; bank 2…
Low
P0021
Powertrain
The bank 2 intake cam is more advanced than commanded or slow to respond; compare it with bank…
Moderate
P0022
Powertrain
The bank 2 intake cam can't advance as far as the PCM asks; phaser, oil pressure or a worn bank…
Moderate
P0024
Powertrain
The bank 2 exhaust cam stays too far advanced or reacts too slowly; check the valve, the oil…
Moderate
P0026
Powertrain
The oil-operated valve control on the bank 1 intake side isn't responding as commanded. Check…
Low
P0028
Powertrain
A bank 2 valve lift solenoid didn't produce the expected result; low or old oil is the most…
Low
P0030
Powertrain
The engine computer found a fault in the heater circuit of the upstream air-fuel sensor on bank…
Low
P0031
Powertrain
The upstream sensor heater on bank 1 draws little or no current – usually an open heater…
Low
P0032
Powertrain
The bank 1 upstream heater circuit looks shorted to power or is drawing far too much current.
Low
P0036
Powertrain
The heater circuit of the oxygen sensor behind the bank 1 catalytic converter is acting…
Minor
P0037
Powertrain
No current flows through the heater of the sensor behind the bank 1 converter – open element…
Minor
P0038
Powertrain
The heater circuit of the sensor behind the bank 1 converter shows a short to power or excess…
Low
P0045
Powertrain
The engine computer sees an open or shorted circuit to the solenoid that controls turbo boost.
Moderate
P0046
Powertrain
The boost control solenoid circuit is intact, but boost doesn't follow what the solenoid…
Moderate
P0050
Powertrain
The heater circuit of the upstream sensor on bank 2 – the side without cylinder 1 – is out…
Low
P0051
Powertrain
The bank 2 upstream sensor heater draws no current: open element, lost feed or broken wire.
Low
P0056
Powertrain
The heater circuit of the sensor behind the bank 2 converter is erratic – typical…
Minor