Fault code lookup

NetworkU1011

Serious

Severity: Serious - have it checked soon

Loss of serial communications for class 2 devices

25 brands affected · Description from GM 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

  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 25

BrandCodeDescriptionSystem
Ashok Leyland CVU1011No description available Network
Mercedes-BenzU1011No description available Network
CheryU1011Abnormal communication between BMU 15 and BMS BrandNetwork
DaewooU1011Loss of serial communications for class 2 devices BrandNetwork
DFFSU1011ECM Lost communication with generator control module LIN BrandNetwork
EOBDU1011Napajanje BrandNetwork
GMU1011Loss of serial communications for class 2 devices BrandNetwork
Great WallU1011Controllable alternator fault BrandNetwork
HoldenU1011No description available Network
HyundaiU1011No description available Network
IsuzuU1011No description available Network
Land RoverU1011is -13 logged BrandNetwork
MahindraU1011No description available Network
MaseratiU1011No description available Network
MitsubishiU1011ACC/FCM Parity/Toggle bit error BrandNetwork
NissanU1011No description available Network
OpelU1011Loss of serial communications for class 2 devices BrandNetwork
PeugeotU1011No description available Network
ProtonU1011ACC/FCM Parity/Toggle bit error BrandNetwork
RenaultU1011No description available Network
SaabU1011Loss of serial communications for class 2 devices BrandNetwork
MG (SAIC)U1011ETC lost Communication With EAC BrandNetwork
SmartU1011No description available Network
SprinterU1011No description available Network
SuzukiU1011CONTROL UNIT (CAN) 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.

5Extended variant codes 1

These 7-character codes are manufacturer-specific variants of U1011 and may be reported by some scan tools.

BrandCodeDescriptionSystem
VolkswagenU101100Supply voltage BrandNetwork

6Related codes

Browse Uxxx codes or U101xx codes.

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