Fault code lookup

NetworkU300D

Serious

Severity: Serious - have it checked soon

Ignition Input On/Start

21 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 21

BrandCodeDescriptionSystem
Ashok Leyland CVU300DIgnition Input On/Start SAENetwork
BAIC MotorU300DIgnition Input On/Start BrandNetwork
BYDU300DIgnition Input On/Start BrandNetwork
CheryU300DIgnition Input On/Start BrandNetwork
DaewooU300DIgnition Input On/Start BrandNetwork
DFFSU300DIgnition Input On/Start BrandNetwork
DFFXU300DIgnition Input On/Start BrandNetwork
DFXKU300DIgnition Input On/Start BrandNetwork
EOBDU300DVhod vklopa/zagon BrandNetwork
GeelyU300DIgnition Input On/Start BrandNetwork
GMU300DIgnition Input On/Start BrandNetwork
Great WallU300DIgnition Input On/Start BrandNetwork
HafeiU300DIgnition Input On/Start BrandNetwork
HoldenU300DIgnition Input On/Start BrandNetwork
HyundaiU300DIgnition Input On/Start SAENetwork
Land RoverU300DIgnition input on/start BrandNetwork
OpelU300DIgnition Input On/Start BrandNetwork
PeugeotU300DIgnition Input On/Start SAENetwork
SaabU300DIgnition Input On/Start BrandNetwork
MG (SAIC)U300DIgnition Input On/Start BrandNetwork
ToyotaU300DIgnition input on/start 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