Welcome to OBD2DTC
Your check engine light is on and a scan tool gave you a five-character code. This site tells you what it means: what the engine computer detected, the likely causes in order, the symptoms you may notice and roughly what a repair costs. Each brand site adds what real owners of that make report, model by model and year by year.
Generic codes explained9,533
Owner complaints analysed159,571
Models with owner data230
Codes owners mention most
Generic codes quoted most often in complaints to NHTSA, all six US-market brands, model years 2012–2025.
| Code | Meaning | Complaints | |
|---|---|---|---|
| P0302 | Cylinder 2 Misfire Detected | 216 | |
| P0420 | Catalyst System Efficiency Below Threshold Bank 1 | 186 | |
| P0303 | Cylinder 3 Misfire Detected | 167 | |
| P0301 | Cylinder 1 Misfire Detected | 154 | |
| P0304 | Cylinder 4 Misfire Detected | 140 | |
| P0300 | Random/Multiple Cylinder Misfire Detected | 112 | |
| P0316 | Engine Misfire Detected on Startup (First 1000 Revolutions) | 112 | |
| P0014 | "B" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1) | 107 | |
| P2112 | Throttle Actuator A Control System - Stuck Closed | 59 | |
| P0017 | Crankshaft Position - Camshaft Position Correlation (Bank 1 Sensor B) | 54 | |
| P0087 | Fuel Rail/System Pressure - Too Low | 51 | |
| P0011 | "A" Camshaft Position - Timing Over-Advanced or System Performance (Bank 1) | 42 |
Code families
| Family | System | Codes |
|---|---|---|
| P0xxx | Powertrain, generic | 3,705 |
| P2xxx | Powertrain, generic (extended) | 3,495 |
| P3xxx | Powertrain, shared range | 155 |
| B0xxx | Body, generic | 323 |
| C0xxx | Chassis, generic | 626 |
| U0xxx | Network, generic | 1,055 |
| U3xxx | Network, generic (extended) | 174 |
How to read a code
The letter is the system: P powertrain, B body, C chassis, U network. A 0 (and most 2) after it means a generic code with the same meaning on every car; a 1 means the manufacturer defined it. Example: P0301 — misfire in cylinder 1.
Brand sites
| Brand | Site | Data |
|---|---|---|
| Toyota | toyota.obd2dtc.org | 39 models · 23,141 owner complaints |
| BMW | bmw.obd2dtc.org | 50 models · 4,598 owner complaints |
| Volkswagen | volkswagen.obd2dtc.org | 35 models · 17,630 owner complaints |
| Ford | ford.obd2dtc.org | 30 models · 46,542 owner complaints |
| Kia | kia.obd2dtc.org | 35 models · 31,055 owner complaints |
| Hyundai | hyundai.obd2dtc.org | 41 models · 36,605 owner complaints |
| Škoda | skoda.obd2dtc.org | 53 models listed |
| Renault | renault.obd2dtc.org | 124 models listed |