NetworkU0046

Serious

Severity: Serious - have it checked soon

Vehicle Communication Bus C

24 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

Wiring or connector fault on the communication bus
Faulty control module
Low battery voltage or poor ground
Water ingress in a connector or module
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 24

Brand	Code	Description	System
Ashok Leyland CV	U0046	Vehicle Communication Bus C SAE	Network
BAIC Motor	U0046	Vehicle Communication Bus C Brand	Network
BYD	U0046	Vehicle Communication Bus C Brand	Network
Chery	U0046	Vehicle Communication Bus C Brand	Network
Daewoo	U0046	Vehicle Communication Bus C Brand	Network
DFFS	U0046	VCAN bus is off Brand	Network
DFFX	U0046	Vehicle Communication Bus C Brand	Network
DFXK	U0046	Vehicle Communication Bus C Brand	Network
EOBD	U0046	Sõiduki sidebuss C Brand	Network
Geely	U0046	Vehicle Communication Bus C Brand	Network
GM	U0046	Vehicle Communication Bus C Brand	Network
Great Wall	U0046	Vehicle Communication Bus C Brand	Network
Hafei	U0046	Vehicle Communication Bus C Brand	Network
Holden	U0046	Radio Private CAN Bus Brand	Network
Hyundai	U0046	Vehicle Communication Bus C SAE	Network
Isuzu	U0046	Vehicle Communication Bus C SAE	Network
Land Rover	U0046	Vehicle Communication Bus C SAE	Network
Mitsubishi	U0046	Vehicle Communication Bus C SAE	Network
Opel	U0046	Vehicle Communication Bus C Brand	Network
Peugeot	U0046	Vehicle Communication Bus C SAE	Network
Saab	U0046	Vehicle Communication Bus C Brand	Network
MG (SAIC)	U0046	Vehicle Communication Bus C SAE	Network
Tata	U0046	Vehicle Communication Bus C Brand	Network
Toyota	U0046	Vehicle communication bus C Brand	Network

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.

5Extended variant codes 2

These 7-character codes are manufacturer-specific variants of U0046 and may be reported by some scan tools.

Brand	Code	Description	System
Mercedes-Benz	U004600	Vehicle Communication Bus C Brand	Network
Mercedes-Benz	U004688	Communication with the drive train sensor CAN bus has a malfunction. Bus OFF Brand	Network

6Related codes

Browse Uxxx codes or U004xx codes.