Fault code lookup

NetworkU0029

Serious

Severity: Serious - have it checked soon

Vehicle Communication Bus A Performance

27 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 27

BrandCodeDescriptionSystem
Ashok Leyland CVU0029Vehicle Communication Bus A Performance SAENetwork
BAIC MotorU0029Vehicle Communication Bus A Performance BrandNetwork
BYDU0029Vehicle Communication Bus A Performance BrandNetwork
CheryU0029CAN 1 communication interrupted BrandNetwork
DaewooU0029Vehicle Communication Bus A Performance BrandNetwork
DFFSU0029Vehicle Communication Bus A Performance BrandNetwork
DFFXU0029Vehicle Communication Bus A Performance BrandNetwork
DFXKU0029Vehicle Communication Bus A Performance BrandNetwork
EOBDU0029Sõiduki sidebussi A jõudlus BrandNetwork
GeelyU0029Vehicle Communication Bus A Performance BrandNetwork
GMU0029Vehicle Communication Bus A Performance BrandNetwork
Great WallU0029Vehicle Communication Bus A Performance BrandNetwork
HafeiU0029Vehicle Communication Bus A Performance BrandNetwork
HoldenU0029MOST Bus Performance BrandNetwork
HondaU0029PA_ minus00_DS BrandNetwork
HyundaiU0029Vehicle Communication Bus A Performance SAENetwork
Land RoverU0029Vehicle communication bus A performance BrandNetwork
MaseratiU0029Vehicle Communication Bus A Performance SAENetwork
OpelU0029Vehicle Communication Bus A Performance BrandNetwork
PeugeotU0029Vehicle Communication Bus A Performance SAENetwork
PorscheU0029Vehicle Communication Bus A Performance SAENetwork
ProtonU0029Vehicle Communication Bus A Performance SAENetwork
SaabU0029Vehicle Communication Bus A Performance BrandNetwork
MG (SAIC)U0029Vehicle Communication Bus A Performance BrandNetwork
TataU0029Vehicle Communication Bus A Performance BrandNetwork
ToyotaU0029Vehicle communication bus A performance BrandNetwork
VolkswagenU0029Sensor / hybrid CAN bus (SAE bus A): performance; No signal/communication 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 U0029 and may be reported by some scan tools.

BrandCodeDescriptionSystem
Mercedes-BenzU002900Drive train CAN bus OFF fault BrandNetwork

6Related codes

Browse Uxxx codes or U002xx codes.

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