Car fault codes explained

What 490 common OBD2 fault codes mean, their usual causes on the makes sold in New Zealand and Australia, and what the repair tends to cost. Codes starting with P are the engine and gearbox, B the body, C the chassis and U the network between the car's computers.

Engine and gearbox (powertrain): P codes

• P0008 Engine position system performance, bank 1: crank and cam timing do…
• P0009 Engine position system performance, bank 2: crank and cam timing do…
• P0010 Electrical fault in the bank 1 intake camshaft timing (VVT) oil…
• P0011 Bank 1 intake cam timing is more advanced than the engine computer…
• P0012 Bank 1 intake cam timing is more retarded than commanded;
• P0013 Exhaust camshaft adjuster (cam magnet) circuit fault, bank 1.
• P0014 Bank 1 exhaust (B) cam timing is over-advanced or the exhaust VVT…
• P0015 Bank 1 exhaust (B) cam timing is more retarded than commanded.
• P0016 Crank and bank 1 intake cam signals are out of step, meaning the cam…
• P0017 Crank and bank 1 exhaust cam signals are out of step.
• P0018 Bank 2 cam and crank timing out of step on Audi V6/V8 engines (e.g.
• P0019 Crank and bank 2 exhaust cam signals are out of step on a V engine.
• P0021 Bank 2 intake cam timing is over-advanced or the bank 2 VVT system is…
• P0024 Exhaust cam timing over-advanced (bank 2) on V6 Jeeps.
• P0026 EJ25 SOHC (i-AVLS) intake valve lift control on the right head is not…
• P0028 EJ25 SOHC (i-AVLS) intake valve lift control on the left head is not…
• P0030 Front (pre-cat) oxygen sensor heater circuit fault, bank 1.
• P0031 Bank 1 upstream oxygen / air-fuel sensor heater circuit reads low,…
• P0032 Front air-fuel ratio sensor heater (bank 1) circuit high.
• P0036 Rear (post-cat) oxygen sensor heater circuit fault, bank 1.
• P0037 Bank 1 downstream (after-cat) oxygen sensor heater circuit reads low.
• P0045 Turbo boost control circuit open: the electronic actuator that moves…
• P0046 Turbo boost control circuit is not performing as expected;
• P004B Turbo boost control B circuit range/performance: on twin-turbo 3.0…
• P0051 Bank 2 upstream oxygen / air-fuel sensor heater circuit reads low (V…
• P0052 Bank 2 upstream oxygen / air-fuel sensor heater circuit reads high (V…
• P0068 Airflow read by the MAF or MAP sensor does not agree with throttle…
• P0069 The manifold pressure (MAP) and barometric pressure readings do not…
• P006A MAP sensor and MAF reading do not agree.
• P007A Charge air cooler (intercooler) temperature sensor circuit.
• P0087 Fuel rail or system pressure is lower than the engine computer wants.
• P0088 Fuel rail pressure is higher than it should be.
• P0089 The fuel pressure regulator is not holding the pressure the engine…
• P0090 Fuel pressure regulator (SCV) control circuit.
• P0093 The engine computer has seen a large fuel leak in the high-pressure…
• P00AF Turbo actuator stuck. On TDI usually seized variable vanes or a…
• P00BD Air flow reading too high for the conditions.
• P0100 Mass air flow (MAF) sensor circuit fault;
• P0101 MAF sensor reading is outside what the engine computer expects for…
• P0102 MAF sensor signal is too low.
• P0103 MAF sensor signal is too high.
• P0106 Manifold absolute pressure (MAP) sensor reading does not make sense…
• P0107 MAP sensor signal is too low.
• P0108 MAP sensor signal is too high.
• P0112 Intake air temperature (IAT) sensor signal is too low (reads very…
• P0113 Intake air temperature (IAT) sensor signal is too high (reads very…
• P0115 Engine coolant temperature (ECT) sensor circuit fault.
• P0116 Coolant temperature reading does not match what the engine computer…
• P0117 Coolant temperature sensor signal is too low (reads very hot).
• P0118 Coolant temperature sensor signal is too high (reads very cold).
• P0120 Throttle position sensor (TPS) A circuit fault.
• P0121 Throttle position sensor A reading does not match other inputs or…
• P0122 Throttle position sensor A signal is too low.
• P0123 Throttle position sensor A signal is too high.
• P0125 Engine is taking too long to get warm enough for closed-loop fuel…
• P0128 Coolant stays below thermostat temperature for too long after…
• P0130 Bank 1 upstream oxygen / air-fuel sensor circuit fault.
• P0131 Bank 1 upstream O2 sensor voltage stays low (reads lean).
• P0132 Bank 1 upstream O2 sensor voltage stays high (reads rich).
• P0133 Bank 1 upstream O2 sensor is slow to respond to mixture changes.
• P0134 Bank 1 upstream O2 sensor shows no activity.
• P0135 Bank 1 upstream O2 sensor heater circuit fault;
• P0136 Bank 1 downstream (after-cat) O2 sensor circuit fault.
• P0137 Bank 1 downstream O2 sensor voltage stays low.
• P0138 Bank 1 downstream O2 sensor voltage stays high.
• P0139 Bank 1 downstream O2 sensor is slow to respond.
• P013A Rear O2 sensor (HO2S) slow to switch from rich to lean on SkyActiv-G.
• P0140 Bank 1 downstream O2 sensor shows no activity.
• P0141 Bank 1 downstream O2 sensor heater circuit fault.
• P0150 Bank 2 upstream O2 / air-fuel sensor circuit fault (V engines).
• P0151 Bank 2 upstream O2 sensor voltage stays low (reads lean).
• P0153 Bank 2 upstream O2 sensor is slow to respond.
• P0155 Bank 2 upstream O2 sensor heater circuit fault.
• P0157 Bank 2 downstream O2 sensor voltage stays low.
• P0158 Bank 2 downstream O2 sensor voltage stays high.
• P0161 Bank 2 downstream O2 sensor heater circuit fault.
• P0170 Bank 1 fuel trim is out of range; the engine computer cannot correct…
• P0171 Bank 1 is running lean (too much air or not enough fuel) and the…
• P0172 Bank 1 is running rich (too much fuel) and the engine computer has…
• P0173 Fuel trim fault, bank 2. On Mercedes V6/V8 most often a dirty or…
• P0174 Bank 2 is running lean. Set together with P0171 it points to a cause…
• P0175 Bank 2 is running rich.
• P0190 Fuel rail pressure sensor circuit fault.
• P0191 Fuel rail pressure sensor reading is outside the expected range.
• P0192 Fuel rail pressure sensor circuit low.
• P0193 Fuel rail pressure sensor signal is too high.
• P0196 Engine oil temperature sensor reading does not make sense.
• P0200 Injector circuit fault. On 1KD/2KD D-4D this is the injector driver…
• P0201 Cylinder 1 fuel injector circuit fault (open or short);
• P0202 Cylinder 2 fuel injector circuit fault.
• P0203 Cylinder 3 fuel injector circuit fault.
• P0204 Cylinder 4 fuel injector circuit fault.
• P0217 Engine overheated. On BMW petrol engines with an electric water pump,…
• P0218 Transmission over temperature: the gearbox fluid has run too hot,…
• P0219 Engine has gone past its maximum safe rpm (over-rev), usually a…
• P0222 Throttle position sensor B signal is too low;
• P0234 Turbo boost pressure has gone higher than the limit (overboost).
• P0236 Boost pressure sensor reading does not match what the engine computer…
• P0237 Boost pressure sensor circuit low.
• P0238 Boost pressure sensor circuit high.
• P0243 Turbo wastegate / boost control solenoid circuit fault.
• P0244 Turbo wastegate (boost control) solenoid range/performance fault on…
• P0251 Injection pump fuel metering control A fault.
• P0261 Cylinder 1 injector circuit reads low.
• P0299 Turbo is not making the boost the engine computer asks for…
• P02CB SkyActiv-D 2.2: large turbo underboost (two-stage turbo).
• P0300 Random or multiple-cylinder misfire. A flashing check light means…
• P0301 Cylinder 1 is misfiring. Swapping the coil to another cylinder shows…
• P0302 Cylinder 2 is misfiring. Swapping the coil to another cylinder shows…
• P0303 Cylinder 3 is misfiring. Swapping the coil to another cylinder shows…
• P0304 Cylinder 4 is misfiring. Swapping the coil to another cylinder shows…
• P0305 Cylinder 5 is misfiring. Swapping the coil to another cylinder shows…
• P0306 Cylinder 6 is misfiring. Swapping the coil to another cylinder shows…
• P0307 Cylinder 7 is misfiring. Swapping the coil to another cylinder shows…
• P0308 Cylinder 8 is misfiring. Swapping the coil to another cylinder shows…
• P0325 Knock sensor 1 (bank 1 or single sensor) circuit fault.
• P0326 Knock sensor 1 signal out of range. On Hyundai engines rule out real…
• P0327 Knock sensor 1 signal is too low.
• P0332 Knock sensor 2 (bank 2) signal is too low (V engines).
• P0335 Crankshaft position sensor circuit fault.
• P0336 Crankshaft position sensor signal is erratic or out of range.
• P0340 Camshaft position sensor circuit fault.
• P0341 Camshaft position sensor signal is out of range or does not line up…
• P0342 Camshaft position sensor A signal is too low.
• P0351 Ignition coil A (usually cylinder 1) primary or secondary circuit…
• P0352 Ignition coil B (usually cylinder 2) primary or secondary circuit…
• P0353 Ignition coil C (usually cylinder 3) primary or secondary circuit…
• P0354 Ignition coil D (usually cylinder 4) primary or secondary circuit…
• P0365 Exhaust camshaft sensor circuit fault (bank 1).
• P0380 Glow plug / heater circuit A fault on a diesel.
• P0400 EGR (exhaust gas recirculation) flow is not as expected.
• P0401 Not enough EGR flow. Very common on diesels and direct-injection…
• P0402 Too much EGR flow; valve likely stuck open.
• P0403 EGR valve control circuit fault.
• P0404 EGR valve position does not match what the engine computer commanded.
• P0405 EGR sensor A circuit low. On 2024 Elantra, Venue and Kona a recall…
• P0406 EGR position sensor circuit high.
• P0409 EGR sensor A circuit.
• P0410 Secondary air injection system fault (cold-start air pump system on…
• P0420 Bank 1 catalytic converter is not cleaning the exhaust well enough.
• P0421 Bank 1 warm-up (front) catalytic converter efficiency is below the…
• P042F EGR valve A stuck closed. Common on 3.0 TDV6 Discovery 4;
• P0430 Bank 2 catalytic converter is not cleaning the exhaust well enough (V…
• P0440 Fault in the EVAP (fuel vapour recovery) system.
• P0441 Incorrect purge flow in the EVAP system;
• P0442 Small leak in the EVAP system.
• P0443 EVAP purge valve circuit fault.
• P0446 EVAP vent valve control circuit or vent system fault.
• P0449 EVAP vent valve / solenoid circuit fault.
• P0455 Large leak in the EVAP system, or no purge flow.
• P0456 Very small leak in the EVAP system.
• P0457 EVAP leak caused by a loose or missing fuel cap.
• P0459 Evap purge control valve circuit reads high (open circuit or short to…
• P0470 Exhaust back-pressure sensor fault on Ranger diesels.
• P0471 Exhaust back-pressure sensor reading is out of range (diesel DPF /…
• P0480 Cooling fan 1 control circuit fault. Fan may not run, so the engine…
• P0489 EGR control circuit low.
• P0491 Secondary air injection system fault, bank 1 (older petrol engines).
• P0496 EVAP purge flow is too high when it should be off;
• P0497 EVAP purge flow lower than expected when the ECU opened the purge…
• P049D EGR valve position outside its learned range.
• P0500 Vehicle speed sensor A fault. Speedo, gear changes and cruise control…
• P0501 Vehicle speed sensor A reading is out of range or does not make sense.
• P0504 The two brake light switch signals disagree.
• P0505 Idle air control system fault; idle speed is not being controlled…
• P0506 Idle speed is lower than the engine computer wants.
• P0507 Idle speed is higher than the engine computer wants.
• P0520 Engine oil pressure sensor / switch circuit fault.
• P0521 Oil pressure reading is out of range.
• P0522 Oil pressure sensor circuit low voltage.
• P0523 Oil pressure sensor circuit high voltage.
• P0524 Engine oil pressure too low. Stop the engine and check oil;
• P0532 A/C refrigerant pressure sensor circuit low.
• P053F Fuel pressure too low during a cold start on direct-injection petrol…
• P0544 Exhaust gas temperature sensor 1 circuit.
• P055F SkyActiv-D: low oil pressure detected by the oil pressure control…
• P0562 System voltage is low. Car may go flat and leave you stranded.
• P0563 System voltage is too high, usually an overcharging alternator.
• P0571 Brake switch A circuit fault. Brake lights and cruise control may be…
• P057F Battery deterioration detected (i-stop battery management).
• P058A Battery current sensor (on the battery negative lead) fault.
• P0597 Electric thermostat heater circuit open.
• P0600 Communication fault between control modules inside or around the…
• P0601 ECM internal memory checksum error.
• P0606 Engine computer (ECM/PCM) processor has failed its self-test.
• P0627 Fuel pump control circuit open. Jeep may crank but not start.
• P062D Fuel injector driver circuit performance (bank 2 on TDV6).
• P0638 Electronic throttle is not reaching the position commanded.
• P0641 Sensor reference voltage A circuit (5 V supply).
• P0651 Sensor reference voltage B circuit (5 V supply).
• P065B Generator (alternator) control circuit range/performance.
• P0670 Glow plug control module circuit fault. Hard cold starts.
• P0671 Cylinder 1 glow plug circuit fault on a diesel.
• P0672 SkyActiv-D: glow plug No.2 circuit fault. Hard cold starts and smoke;
• P0673 SkyActiv-D: glow plug No.3 circuit fault. Hard cold starts and smoke;
• P0674 SkyActiv-D: glow plug No.4 circuit fault. Hard cold starts and smoke;
• P0675 Glow plug circuit fault, cylinder 5. Glow plugs on Mercedes diesels…
• P0676 Glow plug circuit fault, cylinder 6. Glow plugs on Mercedes diesels…
• P0700 Transmission control system fault. This only says the gearbox…
• P0705 Transmission range (PRNDL / inhibitor) sensor circuit fault.
• P0710 Transmission fluid temperature sensor circuit fault.
• P0711 Transmission fluid temperature sensor reading is out of range.
• P0715 Transmission input / turbine speed sensor circuit fault.
• P0717 On Honda automatics: no signal from the mainshaft (input) speed…
• P0718 7G-Tronic turbine speed sensor (Y3/8n1) intermittent;
• P0720 Transmission output speed sensor circuit fault.
• P0722 On Honda automatics: no signal from the countershaft (output) speed…
• P0729 Incorrect 6th gear ratio: the gearbox is slipping in 6th.
• P0730 Incorrect gear ratio; the gearbox is slipping or not in the gear it…
• P0731 Incorrect 1st gear ratio. On the 10R80 the CDF clutch drum sleeve…
• P0732 Incorrect 2nd gear ratio on 2019-on Ranger 10R80: internal slip in…
• P0733 Incorrect 3rd gear ratio on 2019-on Ranger 10R80: slipping in 3rd,…
• P0734 Incorrect 4th gear ratio on the 10R80: slipping in 4th.
• P0735 Incorrect 5th gear ratio on the 10R80: slipping in 5th.
• P0740 Torque converter clutch (lock-up) circuit fault.
• P0741 Torque converter clutch is slipping or not locking up.
• P0743 Damper clutch (torque converter lock-up) solenoid circuit electrical…
• P0744 Torque converter lock-up clutch acting intermittently;
• P0746 Transmission pressure control solenoid performance or stuck off.
• P0748 Pressure control solenoid A electrical/performance fault on the…
• P0750 Shift solenoid A fault.
• P0751 Shift solenoid A performance or stuck off. Harsh or missing shifts.
• P0755 Shift solenoid B fault.
• P0756 Shift solenoid B performance or stuck off.
• P0760 Shift solenoid C fault.
• P0776 Pressure control solenoid B stuck off.
• P0778 Pressure control solenoid B electrical fault (6-speed automatic).
• P0780 Shift fault: the gear ratio after a shift was wrong.
• P0796 Pressure control solenoid C stuck. On 2006-12 Commodore 6L80 auto…
• P0798 7G-Tronic pressure control solenoid C electrical fault;
• P07A3 PowerShift clutch A stuck on: the clutch kept driving when it should…
• P0805 Clutch position sensor circuit (dual-clutch gearbox).
• P0810 DCT clutch position control error. Often only odd or only even gears…
• P0841 Transmission fluid pressure sensor / switch A reading is out of range.
• P0845 IVT (CVT) oil pressure sensor B circuit fault.
• P0847 Honda automatic: short in the 3rd clutch fluid pressure switch…
• P0848 Honda automatic: open circuit in the 3rd clutch fluid pressure…
• P0852 Neutral switch input circuit high (common on Subaru manuals).
• P0867 Transmission fluid pressure fault on the Smartstream IVT (CVT).
• P0868 Transmission line pressure too low. Stop driving: the gearbox can…
• P0882 Transmission control module power supply voltage low.
• P0894 Transmission component slipping. On YF/LF Sonata-type A6MF autos the…
• P0900 Clutch actuator circuit open on the PowerShift (DPS6) dual-clutch in…
• P0901 Clutch actuator circuit range/performance on PowerShift: usually set…
• P0902 Clutch actuator circuit low on PowerShift (DPS6).
• P0903 Clutch actuator circuit high on PowerShift: electrical fault in the…
• P0920 DCT gear shift (forward) actuator circuit fault.
• P0944 Transmission pump lost prime: the gearbox oil pump has stopped…
• P0A0F Engine failed to start: the hybrid system spun the petrol engine with…
• P0A1A Generator control module fault in the hybrid inverter.
• P0A1F Battery energy control module (battery ECU) fault: the hybrid ECU…
• P0A3C Drive motor inverter over temperature (hybrid power control unit).
• P0A78 Drive motor 'A' inverter performance: the inverter section that…
• P0A7A Generator inverter performance: the inverter section that runs the…
• P0A7F Hybrid battery pack deterioration: the pack has lost too much…
• P0A80 Replace hybrid/EV battery pack: the battery ECU sees weak cells.
• P0A93 Inverter cooling system not cooling well enough.
• P0A94 DC/DC (boost) converter performance fault: the voltage in or out of…
• P0A9C Hybrid battery temperature sensor 'A' reading out of range.
• P0AA6 High-voltage isolation fault: leakage between the HV system and the…
• P0C78 PHEV: drive motor inverter capacitor did not pre-charge correctly at…
• P0D22 Outlander PHEV: on-board charger output fault, often logged when an…
• P1014 Volvo code: cam and crank sensor signals do not match.
• P1026 Volvo code: throttle body (electronic throttle module) internal…
• P1028 Volvo code: throttle body internal fault (electronic throttle module).
• P1086 Subaru code: TGV #2 (left) position sensor circuit low.
• P1088 Subaru code: TGV #1 (right) position sensor circuit low.
• P1090 Subaru code: tumble generator valve (TGV) #1, right side, stuck open.
• P1091 Subaru code: tumble generator valve (TGV) #1, right side, stuck…
• P1092 Subaru code: tumble generator valve (TGV) #2, left side, stuck open.
• P1093 Isuzu code: fuel rail pressure too low (rail pressure falls short…
• P10DC Outlander PHEV: engine/generator fail.
• P111A Mazda code: engine coolant temperature is high (overheating).
• P1153 Subaru code: front air-fuel ratio sensor signal out of range (high)…
• P1157 Honda code: front air-fuel ratio (A/F) sensor 1 signal fault…
• P1166 Honda code: front oxygen / air-fuel ratio sensor 1 heater circuit…
• P1167 Honda code: front air-fuel ratio sensor 1 heater system fault.
• P117A Mazda code. SkyActiv-G petrol: engine oil temperature high.
• P1185 Diesel fuel rail pressure above the maximum allowed (CRDi).
• P1187 Diesel fuel pressure regulator valve stuck (CRDi).
• P1190 Freelander 1 Td4 fuel rail pressure plausibility: rail pressure…
• P119A VW group code: high fuel pressure sensor (G247) fault.
• P1200 SkyActiv-D: fuel injection amount learning not completed.
• P1229 Diesel supply pump overfeed (1KD/2KD D-4D): the supply pump is…
• P1247 Land Rover code for turbo boost pressure low, common on Discovery 4 /…
• P1251 Turbo stepper motor/actuator fault on 1KD-FTV Hilux/Prado/Hiace (VN…
• P1259 Honda VTEC system fault. The ECU commanded VTEC (oil-pressure…
• P1295 Electronic throttle control system power management fault;
• P1298 Honda code: electrical load detector (ELD) circuit high voltage.
• P1326 Knock Sensor Detection System (KSDS) has picked up con-rod bearing…
• P1336 Mazda SkyActiv-D code: crank/cam sensor correlation fault.
• P1340 Older Audi code: cam sensor and crank sensor out of step.
• P1347 Older Audi code: bank 2 cam sensor and crank sensor out of step on…
• P1349 VVT system malfunction (bank 1), the Toyota/Lexus code on older VVT-i…
• P1361 Honda code: TDC sensor signal drops out now and then.
• P1362 Honda code: no signal from the TDC sensor.
• P1381 Honda code: cylinder position (CYP) sensor signal drops out now and…
• P1382 Honda code: no signal from the cylinder position (CYP) sensor.
• P1402 Mercedes diesel DPF exhaust pressure sensor fault;
• P1406 Isuzu code: EGR valve position circuit/performance;
• P1408 Suzuki code: manifold differential pressure (MDP) sensor circuit,…
• P1443 Subaru code: evap vent control valve function problem (vent valve…
• P1449 Honda IMA battery module fault: deterioration, overheating or…
• P1450 Suzuki code: barometric pressure sensor circuit fault.
• P1451 Suzuki code: barometric pressure sensor performance.
• P1456 Honda code: EVAP leak on the fuel tank side (fuel cap, filler neck,…
• P1457 Honda code: EVAP leak on the charcoal canister side. Very common;
• P1491 Honda code: EGR valve lift insufficient. On older Honda V6 (e.g.
• P1500 Suzuki code: engine starter signal circuit.
• P1510 Suzuki code: ECM back-up power supply fault.
• P1529 TCM is asking the ECM to turn on the check engine light.
• P1570 Honda IMA code: battery module individual voltage problem.
• P1607 Honda code: engine control module (ECM/PCM) internal circuit fault.
• P1610 Nissan immobiliser (NATS) lock mode: too many start attempts with an…
• P1612 Nissan immobiliser: communication fault between the ECM and the…
• P1614 Nissan immobiliser: immobiliser unit cannot read the key's ID signal,…
• P1693 Immobiliser transponder error: the key isn't being recognised.
• P1705 Honda code: short in the transmission range (gear position) switch…
• P1706 Honda code: open circuit in the transmission range (gear position)…
• P1715 Nissan code: the primary (input) speed signal from the CVT does not…
• P1738 Honda code: 2nd clutch transmission fluid pressure switch circuit…
• P1739 Honda code: 3rd clutch transmission fluid pressure switch circuit…
• P1753 Honda code: torque converter lock-up solenoid valve A circuit fault.
• P175D DSG7 (DQ200) clutch 1 opens when it should not. Loss of drive;
• P1778 CVT step motor function: actual pulley ratio does not follow what the…
• P17BF DSG7 (DQ200 dry clutch) hydraulic pump play protection: the pump runs…
• P17F0 Hyundai IVT/CVT transmission mechanical failure detected.
• P17F1 Hyundai IVT/CVT gear engagement failure.
• P1879 Honda CVT code: fault in the start clutch pressure control valve…
• P1882 Honda CVT code: fault in the inhibitor solenoid circuit.
• P1885 Honda CVT code: drive pulley speed sensor circuit fault.
• P1886 Honda CVT code: driven pulley speed sensor circuit fault.
• P1895 DSG7 (DQ200) hydraulic pressure dropped too low and the clutches let…
• P189A DSG7 (0AM) clutch 1 free play too small.
• P189C DSG7 (DQ200) restricted because hydraulic pressure builds too slowly.
• P1A31 Outlander PHEV: drive battery cell voltage high (battery management…
• P1A90 ICCU (charging unit / DC-DC converter) fault on Ioniq 5 and Ioniq 6.
• P1AAD Outlander PHEV: drive battery current sensor fail.
• P1AF7 Outlander PHEV: fault set when AC (Level 2) charging is attempted,…
• P1E30 Freelander 1 Td4 boost control/control valve fault.
• P2002 Diesel particulate filter (DPF) efficiency is below the limit;
• P2004 Bank 1 intake manifold runner (swirl / tumble) flaps stuck open.
• P2005 Intake runner/swirl flap stuck open, bank 2.
• P2006 Intake runner/swirl flap stuck closed, bank 1.
• P2007 Intake runner/swirl flap stuck closed, bank 2.
• P2008 Intake manifold runner (swirl flap) control circuit open, bank 1.
• P2015 Intake manifold flap (runner) position sensor signal does not make…
• P2032 Exhaust gas temperature sensor 2 circuit low.
• P203F AdBlue level reading too low or level sensor fault.
• P2047 AdBlue injector circuit fault. Injector often blocked by crystallised…
• P2096 Rear O2 sensor shows bank 1 is still lean after the cat, so the…
• P2097 Rear O2 sensor shows bank 1 is still rich after the cat.
• P2098 Post-catalyst fuel trim too lean, bank 2.
• P2099 Post-catalyst fuel trim too rich, bank 2.
• P20B9 AdBlue heater circuit open. The tank/pump heater burning out is a…
• P20E8 AdBlue (DEF) pressure too low. On OM651 BlueTEC often a failed AdBlue…
• P20EE Diesel SCR (AdBlue) NOx catalyst is not reducing NOx enough.
• P2101 Electronic throttle motor is not following the command.
• P2102 Throttle motor circuit shorted to ground. Petrol goes into limp mode;
• P2106 Throttle control forced limited power: the engine computer has put…
• P2110 Throttle control forced limited rpm: the engine is held to low revs…
• P2111 Electronic throttle is stuck open. Car may be hard to slow down;
• P2112 Electronic throttle is stuck closed. Car will have little or no power.
• P2119 Electric throttle body not moving as commanded (return spring fault…
• P2135 The two throttle position sensor signals disagree.
• P2138 The two accelerator pedal position sensor signals disagree.
• P2181 Cooling system performance fault: coolant temperature drops below…
• P2187 Bank 1 is running lean at idle.
• P2188 Bank 1 is running rich at idle.
• P2189 Lean at idle, bank 2 (cylinders 4-6 on a straight six).
• P2195 Bank 1 front O2 / air-fuel sensor signal is stuck lean.
• P2196 Bank 1 front O2 / air-fuel sensor signal is stuck rich.
• P219A Bank 1 air-fuel ratio imbalance between cylinders;
• P2200 NOx sensor circuit fault (diesels with SCR / AdBlue and some…
• P2201 Front NOx sensor reading out of range.
• P2262 SkyActiv-D 2.2: small turbo malfunction detected from boost and…
• P2263 Turbo boost system performance problem;
• P2264 Water in fuel sensor circuit. The water-in-fuel warning system on the…
• P2269 Water in fuel detected. Drain the fuel filter water trap before…
• P2270 Bank 1 rear O2 sensor signal stuck lean.
• P2271 Bank 1 rear O2 sensor signal stuck rich.
• P2279 Intake air system leak; unmetered air is getting into the engine.
• P2288 Fuel injection control pressure too high.
• P2290 Fuel injection control pressure too low.
• P2293 High-pressure fuel regulator cannot hold the pressure asked for.
• P229F NOx sensor (downstream) reading out of range.
• P22D2 Turbo turbine inlet valve stuck open (twin-turbo 3.0 SDV6).
• P2402 Evap leak detection pump (DMTL) control circuit high.
• P240C Gear selector (shift lever) module signal implausible;
• P2418 Evaporative leak diagnostic unit valve signal missing (Volvo EVAP…
• P242F DPF restricted or clogged with ash. Usually needs a DPF clean or…
• P243C SkyActiv-D: DPF is needing regenerations too often (short distance…
• P2440 Secondary air injection switching valve stuck open (cold-start…
• P2442 Secondary air injection switching valve stuck open (bank 2).
• P244A DPF differential pressure is too low (diesels).
• P244B DPF differential pressure is too high;
• P2452 DPF pressure sensor electrical fault.
• P2453 DPF pressure sensor reading is out of range.
• P2456 DPF differential pressure sensor circuit/range.
• P2458 DPF regeneration taking too long: the filter burn-off is not…
• P2459 DPF regenerating too often. Short cold trips and towing are common…
• P2463 DPF is restricted by soot build-up. Needs a regeneration or clean…
• P246C DPF soot load too high on a Ford diesel, with power limited until the…
• P24A4 DPF soot accumulation too high on a Ford diesel.
• P2502 Generator (alternator) output voltage fault.
• P2503 Generator (alternator) output voltage low.
• P252F SkyActiv-D: engine oil level too high.
• P253F SkyActiv-D: engine oil deteriorated (PCM oil-life model says oil is…
• P2562 Turbo boost control position sensor circuit.
• P2563 Turbo actuator position does not match what was asked for.
• P259B Turbo boost control position sensor B performance, stuck high: the…
• P2646 Honda rocker arm (VTEC) oil pressure switch circuit low voltage: the…
• P2647 Honda rocker arm (VTEC) oil pressure switch circuit high voltage: the…
• P2714 Pressure control solenoid 'D' performance/stuck off: the solenoid…
• P2715 Pressure control solenoid D stuck on.
• P2716 7G-Tronic pressure control solenoid D electrical fault;
• P2723 Pressure control solenoid E stuck off.
• P2725 7G-Tronic pressure control solenoid E electrical fault;
• P2734 7G-Tronic pressure control solenoid F electrical fault;
• P2757 Torque converter lock-up pressure control solenoid performance/stuck…
• P2764 Torque converter lock-up solenoid circuit low on the TR580 CVT…
• P2767 7G-Tronic internal speed sensor (Y3/8n2) no signal;
• P2768 7G-Tronic internal speed sensor (Y3/8n2) faulty;
• P2769 Torque converter clutch (lock-up solenoid SL) circuit short on the…
• P2789 Clutch adaptive learning at its limit: the gearbox can no longer…
• P2857 Clutch A pressure engagement fault on the i-DCD 7-speed dual clutch…
• P2A00 Bank 1 front air-fuel ratio sensor reading is out of range or slow.
• P2BAC NOx levels too high because EGR is not working properly (diesel).
• P3000 Battery control system fault: a master code the hybrid ECU sets when…
• P3004 High-voltage power circuit fault on a Toyota hybrid.
• P3006 Hybrid battery state of charge uneven between blocks (early Prius…
• P3009 High-voltage leak detected: current is leaking from the hybrid…
• P3011 Hybrid battery block 1 is weak: its voltage is out of line with the…
• P3012 Hybrid battery block 2 is weak: its voltage is out of line with the…
• P3013 Hybrid battery block 3 is weak: its voltage is out of line with the…
• P3014 Hybrid battery block 4 is weak: its voltage is out of line with the…
• P3015 Hybrid battery block 5 is weak: its voltage is out of line with the…
• P3016 Hybrid battery block 6 is weak: its voltage is out of line with the…
• P3017 Hybrid battery block 7 is weak: its voltage is out of line with the…
• P3018 Hybrid battery block 8 is weak: its voltage is out of line with the…
• P3019 Hybrid battery block 9 is weak: its voltage is out of line with the…
• P3020 Hybrid battery block 10 is weak: its voltage is out of line with the…
• P3021 Hybrid battery block 11 is weak: its voltage is out of line with the…
• P3022 Hybrid battery block 12 is weak: its voltage is out of line with the…
• P3023 Hybrid battery block 13 is weak: its voltage is out of line with the…
• P3024 Hybrid battery block 14 is weak: its voltage is out of line with the…
• P3030 Hybrid battery voltage sense line open circuit (early Prius battery…
• P307A VW group code: air intake flow too low.
• P310B VW group code: low-pressure fuel supply outside spec on…
• P3180 Leaf: VCM has received an error signal from the Li-ion battery…
• P3190 Poor engine power: the engine was asked to run or make power but did…
• P31E7 Leaf: READY restart is blocked after a stored HV fault (usually…
• P324E Toyota hybrid inverter fault code. On 2010-15 Prius it is one of the…
• P33ED Leaf: a battery module has a cell pair with voltage outside limits.
• P3400 Variable Cylinder Management (VCM) cylinder deactivation fault, bank…
• P3497 Variable Cylinder Management (VCM) fault on bank 2 of a Honda V6: the…

Body: B codes

• B0085 Airbag (SRS) fault in a front door circuit.
• B0086 Airbag (SRS) fault in a front door circuit on the other side.

Chassis (brakes, steering, suspension): C codes

• C0047 Subaru VDC/ABS: improper CAN communication.
• C1121 Airmatic body acceleration sensor fault;
• C1123 Airmatic body acceleration sensor fault;
• C1130 Air spring air supply fault (too many top-up events) on Range Rover…
• C1145 Right front wheel speed sensor fault (ABS).
• C1155 Left front wheel speed sensor fault (ABS);
• C1201 Engine control system malfunction: the ABS/VSC computer has switched…
• C1219 Mitsubishi ASC: steering angle sensor signal fault.
• C1241 Low battery voltage at the ABS/VSC (skid control) ECU, roughly under…
• C1253 Brake actuator pump motor/relay fault on Lexus hybrids…
• C1256 Brake accumulator low pressure on Lexus hybrids.
• C1292 All-wheel-drive clutch actuator (quattro, incl.
• C1391 Abnormal leak of brake accumulator pressure on Lexus hybrids.
• C1A00 Air suspension control module fault, often set when ride heights are…
• C1A03 Front left ride height sensor circuit on Discovery 3/4 air…
• C1A06 Rear right ride height sensor on Discovery 3/4 and RR Sport;
• C1A13 Air suspension: pressure does not drop when venting the gallery…
• C1A20 Air suspension: pressure rises too slowly when filling the reservoir.
• C1A27 Air suspension compressor circuit/performance.
• C1A32 Front right air suspension valve block circuit fault on Discovery…
• C1A55 Air suspension ignition switch input circuit on L322 Range Rover;

Network (communication between modules): U codes

• U0001 High-speed CAN bus communication fault;
• U0073 Control module communication bus A is off;
• U0100 Other modules have lost communication with the engine computer…
• U0101 Lost communication with the transmission control module (TCM).
• U0121 Lost communication with the ABS module.
• U0140 Lost communication with the body control module (BCM).
• U0141 CAN time-out from the body computer (ETACS on Mitsubishi).
• U0155 Lost communication with the instrument cluster.
• U0214 Lost communication with the i-stop start stop unit. i-stop disabled.
• U1000 CAN communication fault: a Nissan module lost contact with others on…
• U110A Outlander PHEV: CAN time-out from the PHEV ECU.