Fault code lookup

NetworkU0251

Serious

Severity: Serious - have it checked soon

Lost Communication With Running Board Control Module B

22 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

  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 22

BrandCodeDescriptionSystem
Ashok Leyland CVU0251Lost Communication With Running Board Control Module B SAENetwork
BAIC MotorU0251Lost Communication With Running Board Control Module B BrandNetwork
BYDU0251Lost Communication With Running Board Control Module B BrandNetwork
CheryU0251Lost Communication With Running Board Control Module B BrandNetwork
DaewooU0251Lost Communication With Running Board Control Module B BrandNetwork
DFFSU0251Lost Communication With Running Board Control Module B BrandNetwork
DFFXU0251Lost Communication With Running Board Control Module B BrandNetwork
DFXKU0251Lost Communication With Running Board Control Module B BrandNetwork
EOBDU0251Kaotatud side trepikastimooduliga B BrandNetwork
GeelyU0251Lost Communication With Running Board Control Module B BrandNetwork
GMU0251Lost Communication With Running Board Control Module B BrandNetwork
Great WallU0251Lost Communication With Running Board Control Module B BrandNetwork
HafeiU0251Lost Communication With Running Board Control Module B BrandNetwork
HyundaiU0251Lost Communication With Running Board Control Module B SAENetwork
Land RoverU0251Lost communication with the running board control module B BrandNetwork
MitsubishiU0251AWC CAN(local) timeout BrandNetwork
PeugeotU0251Lost Communication With Running Board Control Module B SAENetwork
ProtonU0251AWC CAN(local) timeout BrandNetwork
SaabU0251Lost Communication With Running Board Control Module B BrandNetwork
Maxus (SAIC)U0251Lost Communication With TIM BrandNetwork
MG (SAIC)U0251Lost Communication With TIM BrandNetwork
ToyotaU0251Lost communication with running board control module B 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.

5Related codes

  • U0250 Lost Communication With Impact Classification System Module
  • U0252 Lost Communication With Lighting Control Module - Rear B
  • U0253 Lost Communication With Accessory Protocol Interface Module
  • U0254 Lost Communication With Remote Start Module
  • U0255 Lost Communication With Front Display Interface Module
  • U0256 Lost Communication With Front Controls Interface Module A
  • U0257 Lost Communication With Front Controls/Display Interface Module
  • U0258 Lost communication with battery cooling system
  • U0259 Lost communication with special purpose vehicle control module 'A'
  • U025A Lost communication with gear P
  • U025B Lost communication with special purpose vehicle control module 'C'
  • U025C Lost Communication With Special Purpose Vehicle Control Module D

Browse Uxxx codes or U025xx codes.

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