NetworkU0203

Serious

Severity: Serious - have it checked soon

Lost Communication With Door Control Module E

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	U0203	Lost Communication With Door Control Module E SAE	Network
BAIC Motor	U0203	Lost Communication With Door Control Module E Brand	Network
BYD	U0203	Lost Communication With Door Control Module E Brand	Network
Chery	U0203	Lost Communication With Door Control Module E Brand	Network
Daewoo	U0203	Lost Communication With Door Control Module E Brand	Network
DFFS	U0203	Lost Communication With Door Control Module E Brand	Network
DFFX	U0203	Lost Communication With Door Control Module E Brand	Network
DFXK	U0203	Lost Communication With Door Control Module E Brand	Network
EOBD	U0203	Kaotatud side ukse juhtimismooduliga E Brand	Network
Geely	U0203	Lost Communication With Door Control Module E Brand	Network
GM	U0203	Lost Communication With Door Control Module E Brand	Network
Great Wall	U0203	Lost Communication With Door Control Module E Brand	Network
Hafei	U0203	Lost Communication With Door Control Module E Brand	Network
Holden	U0203	Lost Communication with Left Rear Door Switch Panel Control Module Brand	Network
Hyundai	U0203	Lost Communication With Door Control Module E SAE	Network
Land Rover	U0203	Lost communication with the door control module E Brand	Network
Maserati	U0203	Lost communication with left front door module Brand	Network
Opel	U0203	Lost Communication With Door Control Module E Brand	Network
Peugeot	U0203	Lost Communication With Door Control Module E SAE	Network
Saab	U0203	Lost Communication With Door Control Module E Brand	Network
MG (SAIC)	U0203	Ecu generic SW problem Brand	Network
Tata	U0203	Lost Communication With 'Door Control Module E' Brand	Network
Toyota	U0203	Lost communication with door control module E Brand	Network
Volkswagen	U0203	SAE: No Communications with Door Control Module E 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 U0203 and may be reported by some scan tools.

Brand	Code	Description	System
Mercedes-Benz	U020382	Communication with control unit 'LEFT FRONT DOOR' has a malfunction. Counter error. Brand	Network
Mercedes-Benz	U020383	Communication with control unit 'LEFT FRONT DOOR' has a malfunction. CRC error. Brand	Network
Mercedes-Benz	U020386	Toggle bit from Door Module failed. - signal invalid Brand	Network
Mercedes-Benz	U020387	Timeout error DM_FL (Door_FL_Stat_AR2) Brand	Network

6Related codes

Browse Uxxx codes or U020xx codes.