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)
P0715
Powertrain
The transmission computer has lost a reliable input-shaft speed signal, so shifts get harsh…
Moderate
P0716
Powertrain
The input speed signal is there but erratic or illogical – dropouts, spikes or values that…
Moderate
P0717
Powertrain
The input speed sensor reports zero while the engine runs and the car moves – the signal…
Moderate
P0720
Powertrain
Electrical fault in the output shaft speed signal – shift timing and sometimes the speedometer…
Moderate
P0722
Powertrain
The output speed sensor sends nothing while the car moves – shifting and often the speedometer…
Moderate
P0730
Powertrain
The transmission computer sees input and output shaft speeds that don't fit the gear it…
High
P0731
Powertrain
While in first gear, the transmission's input and output speeds don't match the first-gear…
Moderate
P0732
Powertrain
Second gear isn't holding: the input-to-output speed ratio in 2nd is outside the expected range.
Moderate
P0733
Powertrain
Third gear slips: input shaft speed doesn't match output speed times the 3rd-gear ratio.
Moderate
P0734
Powertrain
Fourth gear (overdrive on four-speed units) doesn't hold the expected input-to-output speed…
Moderate
P0735
Powertrain
Fifth gear slips or isn't fully applied; the TCM measures a ratio that doesn't fit 5th.
Moderate
P0741
Powertrain
The torque converter lockup clutch slips or won't engage when the computer commands it.
Moderate
P0742
Powertrain
The converter lockup clutch stays applied when it should be released, which can stall…
High
P0744
Powertrain
Lockup control drops in and out: an intermittent TCC circuit, or on some makes a lockup…
Moderate
P0746
Powertrain
Solenoid A doesn't control pressure as commanded: harsh or soft shifts, or limp mode.
Moderate
P0748
Powertrain
The TCM detected an electrical fault (open, short or wrong current) in pressure control…
Moderate
P0750
Powertrain
The transmission computer sees a fault in shift solenoid A or its circuit and can't use it…
Moderate
P0751
Powertrain
Solenoid A is wired fine but its valve isn't doing its job, so gears are missing – often stuck…
High
P0753
Powertrain
The control circuit for shift solenoid A reads open, shorted or out of range – an electrical…
Moderate
P0755
Powertrain
The TCM detects an electrical problem with shift solenoid B, the second on/off shift valve.
Moderate
P0756
Powertrain
Solenoid B isn't moving fluid the way the TCM expects – the car may pull away in 3rd or 4th.
High
P0760
Powertrain
A fault in shift solenoid C's circuit – usually means lost overdrive or upper gears, or limp…
Moderate
P0770
Powertrain
Solenoid E in a five- or six-speed automatic isn't working as commanded: electrical fault…
Moderate
P0773
Powertrain
The transmission computer found an open, short or wrong current in the solenoid E circuit…
Moderate
P0776
Powertrain
Pressure control solenoid B isn't delivering the pressure the TCM asks for – harsh or slipping…
Moderate
P0780
Powertrain
A gear change didn't complete the way the TCM expected, but it can't pin the fault to one part.
Moderate
P0781
Powertrain
The upshift from 1st to 2nd is too slow, slips or never completes properly.
Moderate
P07A3
Ford · Powertrain
The PowerShift's odd-gear clutch isn't letting go when the TCM commands it open, so the car…
High
P0841
Powertrain
Pressure sensor or switch A reports a value that doesn't fit the gear or pressure the TCM…
Moderate
P0868
Powertrain
Measured transmission line pressure is below what the TCM commanded – clutches can slip…
High