Check-engine codes
Find your code, see what it means in plain words, whether you can keep driving, and what the repair usually costs. 180 codes, grouped by the part of the car they point to.
Browse by system
- Engine42 codes. Timing, cooling, idle, throttle and other engine codes.
- Fuel and air26 codes. Fuel trim, air flow and fuel system codes.
- Ignition and misfires17 codes. Misfire and coil codes.
- Emissions54 codes. Catalytic converter, oxygen sensor, EVAP and EGR codes.
- Transmission11 codes. Gear, solenoid and shift codes.
- ABS and brakes10 codes. Wheel speed and anti-lock brake codes.
- Airbag8 codes. Restraint system codes.
- EV and hybrid9 codes. High-voltage battery and hybrid system codes.
- Network3 codes. Modules that stopped talking to each other.
Most searched codes
- P0420
- P0171
- P0300
- P0430
- P0455
- P0456
- P0128
- P0174
- P0301
- P0442
- P0011
- P0014
- P0101
- P0113
- P0172
- P0299
- P0302
- P0303
- P0304
- P0441
- P0700
- P0016
- P0017
- P0340
- P0446
- P0496
- P0102
- P0335
- P0449
- P1101
All codes
| Code | What it means | System |
|---|---|---|
| B0001 | Driver airbag circuit fault | Airbag |
| B0020 | Side or passenger airbag circuit fault | Airbag |
| B0100 | Front impact sensor circuit fault | Airbag |
| B1000 | Airbag control module internal fault | Airbag |
| B1318 | Low battery voltage at restraint module | Airbag |
| B1325 | Restraint system voltage or circuit fault | Airbag |
| B1342 | Control module fault (airbag or body) | Airbag |
| B1421 | Restraint circuit fault (varies by make) | Airbag |
| C0031 | Left front wheel speed sensor signal fault | ABS and brakes |
| C0035 | Left front wheel speed sensor signal fault | ABS and brakes |
| C0040 | Right front wheel speed sensor signal fault | ABS and brakes |
| C0045 | Left rear wheel speed sensor signal fault | ABS and brakes |
| C0110 | ABS pump motor circuit fault | ABS and brakes |
| C0161 | ABS or traction brake switch circuit fault | ABS and brakes |
| C0265 | ABS motor relay circuit fault | ABS and brakes |
| C0300 | Rear wheel speed sensor signal fault | ABS and brakes |
| C0561 | ABS system disabled or module fault | ABS and brakes |
| C1201 | Engine control fault shown on ABS side | ABS and brakes |
| P0011 | Intake camshaft timing too far advanced (bank 1) | Engine |
| P0012 | Intake camshaft timing too far behind (bank 1) | Engine |
| P0013 | Exhaust camshaft timing stuck (bank 1) | Engine |
| P0014 | Exhaust camshaft timing too far advanced (bank 1) | Engine |
| P0016 | Crankshaft and camshaft not lining up (bank 1) | Engine |
| P0017 | Crankshaft and exhaust camshaft not lining up (bank 1) | Engine |
| P0021 | Intake camshaft timing over-advanced (bank 2) | Engine |
| P0030 | Oxygen sensor heater circuit fault (bank 1, before converter) | Emissions |
| P0031 | Oxygen sensor heater circuit low (bank 1, before converter) | Emissions |
| P0032 | Upstream oxygen sensor heater control high (bank 1) | Emissions |
| P0036 | Oxygen sensor heater circuit fault (bank 1, after converter) | Emissions |
| P0037 | Oxygen sensor heater circuit low (bank 1, after converter) | Emissions |
| P0038 | Downstream oxygen sensor heater control circuit high (bank 1) | Emissions |
| P0050 | Upstream oxygen sensor heater control problem (bank 2) | Emissions |
| P0051 | Upstream oxygen sensor heater control low (bank 2) | Emissions |
| P0053 | Upstream oxygen sensor heater resistance wrong (bank 1) | Emissions |
| P0087 | Fuel pressure too low | Fuel and air |
| P0089 | Fuel pressure regulator not holding correct pressure | Fuel and air |
| P0101 | Air flow sensor reading seems off | Fuel and air |
| P0102 | Air flow sensor signal too low | Fuel and air |
| P0103 | Mass airflow sensor reads too high | Fuel and air |
| P0106 | Manifold pressure sensor reading doesn't match | Fuel and air |
| P0107 | Manifold pressure sensor reads low | Fuel and air |
| P0108 | Manifold pressure sensor signal too high | Fuel and air |
| P0113 | Intake air temperature signal too high | Fuel and air |
| P0117 | Coolant temperature signal too low | Engine |
| P0118 | Coolant temperature signal too high | Engine |
| P0121 | Throttle position reading doesn't match | Engine |
| P0122 | Throttle position signal too low | Engine |
| P0123 | Throttle position sensor A reads high | Engine |
| P0125 | Engine slow to warm up for normal fuel control | Engine |
| P0128 | Engine not warming up fast enough | Engine |
| P0130 | Upstream oxygen sensor circuit problem (bank 1) | Emissions |
| P0131 | Oxygen sensor reads low voltage (bank 1, before converter) | Emissions |
| P0132 | Oxygen sensor reads high voltage (bank 1, sensor 1) | Emissions |
| P0133 | Oxygen sensor responding slowly (bank 1, before converter) | Emissions |
| P0134 | Oxygen sensor not responding (bank 1, before converter) | Emissions |
| P0135 | Oxygen sensor heater fault (bank 1, before converter) | Emissions |
| P0136 | Downstream oxygen sensor circuit problem (bank 1) | Emissions |
| P0137 | Rear oxygen sensor reads low (bank 1, after converter) | Emissions |
| P0138 | Rear oxygen sensor reads high (bank 1, after converter) | Emissions |
| P0139 | Downstream oxygen sensor slow to respond (bank 1) | Emissions |
| P0140 | Downstream oxygen sensor shows no activity (bank 1) | Emissions |
| P0141 | Oxygen sensor heater fault (bank 1, after converter) | Emissions |
| P0151 | Upstream oxygen sensor voltage too low (bank 2) | Emissions |
| P0153 | Upstream oxygen sensor slow to respond (bank 2) | Emissions |
| P0155 | Upstream oxygen sensor heater circuit problem (bank 2) | Emissions |
| P0157 | Rear oxygen sensor reads low (bank 2, after converter) | Emissions |
| P0158 | Downstream oxygen sensor reads high voltage (bank 2) | Emissions |
| P0161 | Oxygen sensor heater fault (bank 2, after converter) | Emissions |
| P0171 | Engine getting too much air or too little fuel (bank 1) | Fuel and air |
| P0172 | Engine getting too much fuel (bank 1) | Fuel and air |
| P0174 | Engine getting too much air or too little fuel (bank 2) | Fuel and air |
| P0175 | Engine getting too much fuel (bank 2) | Fuel and air |
| P0191 | Fuel rail pressure sensor reading off | Fuel and air |
| P0193 | Fuel rail pressure sensor reads high | Fuel and air |
| P0201 | Cylinder 1 injector circuit problem | Fuel and air |
| P0234 | Turbo boost pressure too high | Fuel and air |
| P0299 | Turbo not making enough boost | Fuel and air |
| P0300 | Random or multiple cylinder misfires | Ignition and misfires |
| P0301 | Cylinder 1 misfire | Ignition and misfires |
| P0302 | Cylinder 2 misfire | Ignition and misfires |
| P0303 | Cylinder 3 misfire | Ignition and misfires |
| P0304 | Cylinder 4 misfire | Ignition and misfires |
| P0305 | Cylinder 5 misfire | Ignition and misfires |
| P0306 | Cylinder 6 misfire | Ignition and misfires |
| P0307 | Cylinder 7 misfire | Ignition and misfires |
| P0308 | Cylinder 8 misfire | Ignition and misfires |
| P0316 | Misfire detected during startup | Ignition and misfires |
| P0325 | Knock sensor circuit fault (bank 1) | Ignition and misfires |
| P0327 | Knock sensor signal too low (bank 1) | Engine |
| P0328 | Knock sensor signal too high (bank 1) | Engine |
| P0335 | Crankshaft position sensor circuit fault | Engine |
| P0336 | Crankshaft position sensor out of range | Engine |
| P0340 | Camshaft position sensor circuit fault | Engine |
| P0341 | Camshaft position signal out of range | Engine |
| P0344 | Camshaft position sensor A signal dropping out (bank 1) | Engine |
| P0351 | Ignition coil A circuit problem | Ignition and misfires |
| P0352 | Ignition coil B circuit problem | Ignition and misfires |
| P0353 | Ignition coil C circuit problem | Ignition and misfires |
| P0354 | Ignition coil D circuit problem | Ignition and misfires |
| P0355 | Ignition coil E circuit problem | Ignition and misfires |
| P0356 | Ignition coil F circuit problem | Ignition and misfires |
| P0365 | Camshaft position sensor B circuit problem (bank 1) | Engine |
| P0401 | Exhaust gas recirculation flow too low | Emissions |
| P0402 | Exhaust recirculation flow too high | Emissions |
| P0403 | Exhaust recirculation valve control circuit problem | Emissions |
| P0404 | Exhaust recirculation system not working as commanded | Emissions |
| P0410 | Secondary air system fault | Emissions |
| P0411 | Secondary air system flow not right | Emissions |
| P0420 | Catalytic converter not working well (bank 1) | Emissions |
| P0421 | Catalytic converter slow to clean up after warm-up (bank 1) | Emissions |
| P0430 | Catalytic converter not working well (bank 2) | Emissions |
| P0440 | Fuel vapor system problem | Emissions |
| P0441 | Fuel vapor purge flow wrong | Emissions |
| P0442 | Small fuel vapor leak | Emissions |
| P0443 | Purge valve circuit problem | Emissions |
| P0446 | Fuel vapor vent circuit problem | Emissions |
| P0449 | Fuel vapor vent valve circuit problem | Emissions |
| P0452 | Fuel vapor system pressure sensor reads low | Emissions |
| P0453 | Fuel vapor pressure sensor signal too high | Emissions |
| P0455 | Large fuel vapor leak | Emissions |
| P0456 | Very small fuel vapor leak | Emissions |
| P0457 | Fuel vapor leak, gas cap may be loose | Emissions |
| P0463 | Fuel level sensor reading too high | Fuel and air |
| P0480 | Cooling fan 1 control circuit problem | Engine |
| P0491 | Secondary air system flow too low (bank 1) | Emissions |
| P0496 | Fuel vapor purge flow while engine off | Emissions |
| P0500 | Vehicle speed sensor signal problem | Transmission |
| P0505 | Idle control system problem | Engine |
| P0506 | Idle speed lower than expected | Engine |
| P0507 | Engine idle higher than expected | Engine |
| P0520 | Engine oil pressure sensor circuit problem | Engine |
| P0521 | Oil pressure sensor signal out of range | Engine |
| P0522 | Engine oil pressure sensor reads too low | Engine |
| P0523 | Engine oil pressure sensor reads too high | Engine |
| P0562 | System voltage low | Engine |
| P0603 | Engine computer memory fault | Engine |
| P0606 | Engine computer processor fault | Engine |
| P0641 | Sensor 5-volt supply A circuit problem | Engine |
| P0700 | Transmission computer reports a fault | Transmission |
| P0705 | Transmission range sensor circuit problem | Transmission |
| P0717 | Input speed sensor gives no signal | Transmission |
| P0720 | Transmission output speed sensor problem | Transmission |
| P0731 | First gear ratio incorrect | Transmission |
| P0740 | Torque converter clutch circuit problem | Transmission |
| P0741 | Torque converter clutch not locking | Transmission |
| P0746 | Pressure control solenoid A stuck off | Transmission |
| P0776 | Transmission pressure solenoid B stuck off | Transmission |
| P0868 | Transmission fluid pressure low | Transmission |
| P0A0D | High voltage interlock circuit open | EV and hybrid |
| P0A0F | Engine failed to start in hybrid system | EV and hybrid |
| P0A78 | Drive motor inverter performance problem | EV and hybrid |
| P0A7F | Hybrid battery pack deterioration | EV and hybrid |
| P0A80 | Hybrid battery weak or worn out | EV and hybrid |
| P0A93 | Inverter cooling system problem | EV and hybrid |
| P0A94 | DC/DC converter performance problem | EV and hybrid |
| P0AA6 | High voltage isolation fault | EV and hybrid |
| P0AFA | Hybrid battery voltage low | EV and hybrid |
| P1000 | Emissions self-tests not finished yet | Emissions |
| P1101 | Airflow sensor out of expected range | Fuel and air |
| P1299 | Cylinder head overheat protection active | Engine |
| P1450 | Fuel tank vacuum problem | Emissions |
| P2096 | Fuel mix too lean after catalytic converter (bank 1) | Fuel and air |
| P2097 | Fuel mix too rich after catalytic converter (bank 1) | Fuel and air |
| P2098 | Post-catalyst fuel trim too lean (bank 2) | Fuel and air |
| P2099 | Post-catalyst fuel trim too rich (bank 2) | Fuel and air |
| P2101 | Throttle actuator motor performance problem | Engine |
| P2122 | Accelerator pedal sensor D signal too low | Engine |
| P2135 | Throttle position sensors disagree | Engine |
| P2138 | Accelerator pedal sensors disagree | Engine |
| P2187 | System too lean at idle (bank 1) | Fuel and air |
| P2195 | Upstream oxygen sensor stuck lean (bank 1) | Emissions |
| P2196 | Oxygen sensor stuck rich (bank 1, before converter) | Fuel and air |
| P2198 | Upstream oxygen sensor stuck rich (bank 2) | Emissions |
| P2270 | Downstream oxygen sensor stuck lean (bank 1) | Emissions |
| P2509 | Engine computer power supply on and off | Engine |
| P2646 | Rocker arm actuator A performance problem | Engine |
| P2647 | Rocker arm actuator B stuck or performing poorly | Engine |
| U0073 | Control module communication bus off | Network |
| U0100 | Lost communication with engine computer | Network |
| U0121 | Lost communication with ABS module | Network |
Code names and meanings are written in our own words. Some codes mean different things on different makes; check your scan tool or manual if the description does not fit your car.
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