NetworkU1104

Serious

Severity: Serious - have it checked soon

Transport mode

30 brands affected · Description from Toyota data.

Key terms: Control module: a small computer that runs one part of the car

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 30

Brand	Code	Description	System
BAIC Motor	U1104	Received BCM signal abnormal Brand	Network
Mercedes-Benz	U1104	No description available	Network
BYD	U1104	SAS CAN timeout/Not equipped Brand	Network
Chery	U1104	SAS CAN timeout/Not equipped Brand	Network
Daewoo	U1104	Loss of serial communications for class 2 devices Brand	Network
Daihatsu	U1104	PCS signal abnormal Brand	Network
DFFX	U1104	SAS CAN timeout/Not equipped Brand	Network
EOBD	U1104	Modh Iompair Brand	Network
Geely	U1104	SAS CAN timeout/Not equipped Brand	Network
GM	U1104	Loss of serial communications for class 2 devices Brand	Network
Great Wall	U1104	SAS CAN timeout/Not equipped Brand	Network
Hafei	U1104	SAS CAN timeout/Not equipped Brand	Network
Holden	U1104	No description available	Network
Honda	U1104	No description available	Network
Isuzu	U1104	No description available	Network
Mahindra	U1104	No description available	Network
Maserati	U1104	No description available	Network
Mitsubishi	U1104	SAS CAN timeout/Not equipped Brand	Network
Opel	U1104	Loss of serial communications for class 2 devices Brand	Network
Perodua	U1104	PCS signal abnormal Brand	Network
Peugeot	U1104	No description available	Network
Porsche	U1104	No description available	Network
Proton	U1104	SAS CAN timeout/Not equipped Brand	Network
Saab	U1104	Loss of serial communications for class 2 devices Brand	Network
MG (SAIC)	U1104	Time Out Steering angle Sensor related Data Brand	Network
Smart	U1104	No description available	Network
Sprinter	U1104	No description available	Network
Suzuki	U1104	Lost Communication With Active Cruise Control Module Brand	Network
Tata	U1104	ECU Interior Communication Abnormal/Communication Error B Brand	Network
Toyota	U1104	Transport mode 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 4

These 7-character codes are manufacturer-specific variants of U1104 and may be reported by some scan tools.

Brand	Code	Description	System
Volkswagen	U110400	Extended bus mode active Brand	Network
SsangYong	U110402	CAN communication: BS_300 communication error - timeout Brand	Network
Mercedes-Benz	U110408	Die Kommunikation mit der Endstufe 'Differenzialsperre an der Hinterachse' hat Funktionsstörung. Es liegt ein Signalfehler vor oder die Botschaft ist fehlerhaft. Brand	Network
SsangYong	U110487	CAN communication: Battery Management System (BMS) message not received Brand	Network

6Related codes

Browse Uxxx codes or U110xx codes.