DTC codes
Look up an OBD-II fault code: what it means on every car or on your make, and how to track it down.
How to read a code
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 4
- AreaAuxiliary emission controls
- 20
- FaultThe specific fault in that area
Read the code
Note every stored and pending code your scanner shows, such as P0420.
Find it
Search by code or by words. For a manufacturer code (P1, B1, C1, U1) pick your make: its meaning differs by make.
Open the code
Its page explains the symptoms, likely causes, the checks to run and the fixes.
- U034DGeneric · NetworkSoftware Incompatibility With Vehicle Thermal Management Control Module
- U034EGeneric · NetworkSoftware Incompatibility With Active Grille Air Shutter Module A
- U034FGeneric · NetworkSoftware Incompatibility With Active Grille Air Shutter Module B
- U0350Generic · NetworkSoftware Incompatibility With Active Grille Air Shutter Module C
- U0351Generic · NetworkSoftware Incompatibility With Active Grille Air Shutter Module D
- U0352Generic · NetworkSoftware Incompatibility With NOx Sensor C
- U0353Generic · NetworkSoftware Incompatibility With Ion Sense Module
- U0354Generic · NetworkSoftware Incompatibility With Hybrid/EV Battery Inductive Charger Control Module
- U0400Generic · NetworkInvalid Data Received
- U0401Generic · NetworkInvalid Data Received From ECM/PCM A
- U0402Generic · NetworkInvalid Data Received From TCM
- U0403Generic · NetworkInvalid Data Received From Transfer Case Control Module
- U0404Generic · NetworkInvalid Data Received From Gear Shift Control Module A
- U0405Generic · NetworkInvalid Data Received From Cruise Control Module
- U0406Generic · NetworkInvalid Data Received From Fuel Injector Control Module
- U0407Generic · NetworkInvalid Data Received From Glow Plug Control Module 1
- U0408Generic · NetworkInvalid Data Received From Throttle Actuator A Control Module
- U0409Generic · NetworkInvalid Data Received From Alternative Fuel Control Module
- U040AGeneric · NetworkInvalid Data Received From Air Conditioning Control Module
- U040BGeneric · NetworkInvalid Data Received From Exhaust Gas Recirculation Control Module A
- U040CGeneric · NetworkInvalid Data Received From Exhaust Gas Recirculation Control Module B
- U040DGeneric · NetworkInvalid Data Received From Turbocharger/Supercharger Control Module A
- U040EGeneric · NetworkInvalid Data Received From Turbocharger/Supercharger Control Module B
- U040FGeneric · NetworkInvalid Data Received From Reductant Control Module
- U0410Generic · NetworkInvalid Data Received From Fuel Pump Control Module A
- U0411Generic · NetworkInvalid Data Received From Drive Motor Control Module A
- U0412Generic · NetworkInvalid Data Received From Battery Energy Control Module A
- U0413Generic · NetworkInvalid Data Received From Battery Energy Control Module B
- U0414Generic · NetworkInvalid Data Received From Four-Wheel Drive Clutch Control Module
- U0415Generic · NetworkInvalid Data Received From Anti-Lock Brake System (ABS) Control Module
