Fault code lookup

NetworkU3FFF

Serious

Severity: Serious - have it checked soon

CAN-Bus (Low Speed) Communication Malfunction

11 brands affected · Description from Daewoo 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 11

BrandCodeDescriptionSystem
DaewooU3FFFCAN-Bus (Low Speed) Communication Malfunction BrandNetwork
DFFSU3FFFPowertrain failure BrandNetwork
GMU3FFFNo description available Network
HoldenU3FFFNo description available Network
HondaU3FFFNo description available Network
MitsubishiU3FFFNo description available Network
OpelU3FFFNo description available Network
PeugeotU3FFFNo description available Network
ProtonU3FFFNo description available Network
SaabU3FFFNo description available Network
SubaruU3FFFNo description available 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 11

These 7-character codes are manufacturer-specific variants of U3FFF and may be reported by some scan tools.

BrandCodeDescriptionSystem
SsangYongU3FFF00ECU 0 absent (ABS/ESP) BrandNetwork
SsangYongU3FFF01ECU 1 absent (TCU) BrandNetwork
SsangYongU3FFF02ECU 3 absent (cluster) BrandNetwork
SsangYongU3FFF03ECU 4 absent (GCU) BrandNetwork
SsangYongU3FFF04ECU 5 absent (ECM) BrandNetwork
Mercedes-BenzU3FFF10Invalid Certificate Chain. BrandNetwork
Mercedes-BenzU3FFF12No description available Network
SprinterU3FFF12No description available Network
Mercedes-BenzU3FFFEBNo description available Network
Mercedes-BenzU3FFFFEService: For Service not relevant: DTC_DET_ReportError or SMM_OneRequestsInit BrandNetwork
Mercedes-BenzU3FFFFFNo description available Network

6Related codes

Browse Uxxx codes or U3FFxx codes.

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