OBD
OBDIICSU
OBD-II Diagnostic Trouble Code Database

OBD-II Code Lookup

Enter a trouble code from your scanner to see what it means, why it happens, and what to check first.

Browse all codes →
3,395
Diagnostic Codes
4
Code Families
1,446
P · Powertrain
✓
Continuously Maintained

Most searched codes

P0300
Random/Multiple Cylinder Misfire Detected
P0420
Catalyst System Efficiency Below Threshold (Bank 1)
P0171
System Too Lean (Bank 1)
P0455
Evaporative Emission Control System Tank Detected (gross leak)
P0700
Transmission Control System Malfunction
P0442
Evaporative Emission Control System leak Detected (small leak)
P0401
Exhaust Gas Recirculation Flow Insufficient Detected
P0113
Intake Air Temperature Circuit High Input
P0011
A Camshaft Position – Timing Over-Advanced or System Performance (Bank 1)
U1000
SCP (J1850) Invalid or Missing Data for Primary Id
C1201
ABS Inlet Valve Coil LF Circuit Short To Ground

Browse OBD-II codes

P
Powertrain · 1,446
Engine, transmission, fuel and emissions systems
B
Body · 1,164
Body electronics — airbags, climate control, lighting and interior systems
C
Chassis · 486
Chassis systems — braking (ABS), steering, suspension and traction control
U
Network · 299
Network communication between the vehicle’s onboard control modules

How to read an OBD-II code

Every OBD-II trouble code follows the same five-character format. The first character tells you which system is affected, and the rest narrows down the exact fault.

The first letter — which system

  • P — Powertrain: engine, transmission, fuel and emissions.
  • B — Body: airbags, climate control, lighting and interior electronics.
  • C — Chassis: braking (ABS), steering, suspension and traction.
  • U — Network: communication between the vehicle’s control modules.

The second digit — generic or manufacturer-specific

A 0 means the code is generic and standardised across all vehicles. A 1 means it is specific to your make. The remaining digits identify the exact subsystem and fault.