Fault code lookup

NetworkU0303

Serious

Severity: Serious - have it checked soon

Software Incompatibility With Transfer Case Control Module

23 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 23

BrandCodeDescriptionSystem
Ashok Leyland CVU0303Software Incompatibility With Transfer Case Control Module SAENetwork
BAIC MotorU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
BYDU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
CheryU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
DaewooU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
DFFSU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
DFFXU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
DFXKU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
EOBDU0303Software-incompatibiliteit met regelmodule tussenbak BrandNetwork
GeelyU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
GMU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
Great WallU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
HafeiU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
HoldenU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
HyundaiU0303Software Incompatibility With Transfer Case Control Module SAENetwork
Land RoverU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
OpelU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
PeugeotU0303Software Incompatibility With Transfer Case Control Module SAENetwork
SaabU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
MG (SAIC)U0303Software Incompatibility With Transfer Case Control Module BrandNetwork
TataU0303Software Incompatibility With Transfer Case Control Module BrandNetwork
ToyotaU0303Software incompatibility with transfer case control module BrandNetwork
VolkswagenU0303SAE: Software Incompatibility with Transfer Case Control Module 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 U030xx codes.

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