Fault code lookup

NetworkU300F

Serious

Severity: Serious - have it checked soon

Ignition Input Accessory

22 brands affected · Generic SAE J2012 description.

Key terms: Control module: a small computer that runs one part of the car · SAE J2012: the standard generic code list

1What it means in plain English

Control modules in the car cannot communicate with each other over the vehicle network.

2Common causes

  1. Wiring or connector fault on the communication bus
  2. Faulty control module
  3. Low battery voltage or poor ground
  4. Water ingress in a connector or module
  5. Aftermarket device interfering with the bus

3Can I drive?

Serious · drive with care

The car may run normally or may not run at all. If the module that has lost communication controls steering, brakes, park brake, charging or engine cooling, drive only if those systems feel normal; stop safely if the steering becomes heavy, a brake warning appears, or the engine temperature climbs. If the car will not start or runs badly, have it towed.

This page gives general information. It is not professional advice. For a definite diagnosis and a repair quote, ask a qualified mechanic to inspect the car.

4Brand data 22

BrandCodeDescriptionSystem
Ashok Leyland CVU300FDC/DC Converter. Voltage Sensor. (Sensor A.) - High Signal BrandNetwork
BAIC MotorU300FIgnition Input Accessory BrandNetwork
Mercedes-BenzU300FIgnition Input Accessory SAENetwork
BYDU300FIgnition Input Accessory BrandNetwork
CheryU300FIgnition Input Accessory BrandNetwork
DaewooU300FIgnition Input Accessory BrandNetwork
DFFSU300FIgnition Input Accessory BrandNetwork
DFFXU300FIgnition Input Accessory BrandNetwork
DFXKU300FIgnition Input Accessory BrandNetwork
EOBDU300FContactingang accessoire BrandNetwork
GeelyU300FIgnition Input Accessory BrandNetwork
GMU300FIgnition Input Accessory BrandNetwork
Great WallU300FIgnition Input Accessory BrandNetwork
HafeiU300FIgnition Input Accessory BrandNetwork
HoldenU300FIgnition Input Accessory BrandNetwork
HyundaiU300FIgnition Input Accessory SAENetwork
Land RoverU300FIgnition input accessory BrandNetwork
OpelU300FIgnition Input Accessory BrandNetwork
PeugeotU300FIgnition Input Accessory SAENetwork
SaabU300FIgnition Input Accessory BrandNetwork
MG (SAIC)U300FIgnition Input Accessory BrandNetwork
ToyotaU300FIgnition input accessory BrandNetwork

Legend: SAE is the generic J2012 description; Brand is text taken from that manufacturer’s data. Manufacturer rows keep the wording and language of the source data, and non-English text is tagged so screen readers pronounce it correctly.

5Related codes

Browse Uxxx codes or U300xx codes.

OpenDTC - independent fault code reference