Fault code lookup

NetworkU1120

Serious

Severity: Serious - have it checked soon

Lost wheel distance message

24 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

  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 24

BrandCodeDescriptionSystem
Mercedes-BenzU1120No description available Network
BYDU1120Engine BrandNetwork
CheryU1120Engine BrandNetwork
DaewooU1120Loss of serial communications for class 2 devices BrandNetwork
DaihatsuU1120Lost communication with object recognition camera BrandNetwork
DFFSU1120Vehicle CAN message 0x30D receiving failure BrandNetwork
DFFXU1120Engine BrandNetwork
EOBDU1120No description available Network
GeelyU1120Engine BrandNetwork
GMU1120Loss of serial communications for class 2 devices BrandNetwork
Great WallU1120Engine BrandNetwork
HafeiU1120Engine BrandNetwork
IsuzuU1120No description available Network
MahindraU1120No description available Network
MitsubishiU1120Engine BrandNetwork
PeroduaU1120Lost communication with object recognition camera BrandNetwork
PeugeotU1120No description available Network
ProtonU1120Engine BrandNetwork
SaabU1120Loss of serial communications for class 2 devices BrandNetwork
SmartU1120No description available Network
SprinterU1120Valid except code 852 BrandNetwork
SubaruU1120No description available Network
SuzukiU1120AV SWITCH SIGNAL BrandNetwork
ToyotaU1120Lost wheel distance message 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 15

These 7-character codes are manufacturer-specific variants of U1120 and may be reported by some scan tools.

BrandCodeDescriptionSystem
SsangYongU112002CAN communication: MCU_3A3 communication error - timeout BrandNetwork
Mercedes-BenzU112004The security module of the control unit has detected a communication error. There is an internal fault. BrandNetwork
Mercedes-BenzU112041The security module of the control unit has detected a communication error. General checksum failure. BrandNetwork
Mercedes-BenzU112081Time sync message invalid (IT-Security) BrandNetwork
Mercedes-BenzU112083SecOC calculation incorrect (IT-Security) BrandNetwork
Mercedes-BenzU112087The security module of the control unit has detected a communication error. BrandNetwork
Mercedes-BenzU112088Time sync message missing. BrandNetwork
Mercedes-BenzU1120E0Ethernet Inter Processor Communication Containers are dropped on uC BrandNetwork
Mercedes-BenzU1120E1Ethernet Inter Processor Communication Containers are dropped on uP BrandNetwork
Mercedes-BenzU1120E8uP is not booting correctly. BrandNetwork
Mercedes-BenzU1120E9uP Software unexepcted software behaviour. BrandNetwork
Mercedes-BenzU1120EBThe security module of the control unit has detected a communication error. Software lockstep security error dectected on master BrandNetwork
Mercedes-BenzU1120FACommunication with control unit FAA has a malfunction BrandNetwork
Mercedes-BenzU1120FBImplausible object data were received from FAA status BrandNetwork
Mercedes-BenzU1120FCCommunication with control unit HWA has a malfunction. BrandNetwork

6Related codes

Browse Uxxx codes or U112xx codes.

OpenDTC - independent fault code reference