U0140 on Alfa Romeo
Lost Communication with BCM
U0140 on Alfa Romeo vehicles indicates lost communication with bcm. Au7o has documented this code across 1 Alfa Romeo model — most commonly on Giulia. U0140 is a network communication code meaning a module has lost communication with the body control module (BCM) over the vehicle's data bus. The BCM oversees many body and convenience functions — lighting, door locks, windows, wipers, anti-theft, and gateway communications — so losing contact with it can cause a wide range of seemingly unrelated electrical problems and warning lights. This is typically a wiring, connector, power/ground, or bus fault, or a failure of the BCM itself. Because the BCM often acts as a communication hub, this code can appear alongside other 'lost communication' codes. Typical repair costs on Alfa Romeo range from $300 to $1,500, depending on the specific model and root cause.
Common Causes of U0140
- •Loss of power or ground to the BCM
- •CAN/data bus wiring damage, short, or open circuit
- •Corroded, loose, or damaged BCM connectors
- •Blown fuse feeding the BCM
- •Failed body control module
- •Water intrusion or corrosion in the harness
- •Another module faulting the shared data bus
U0140 on Alfa Romeo by Model
Alfa Romeo Giulia(1 issue)
- Electrical Faults from Water Intrusion / BCM Failure2017-2022
Water enters the cowl/firewall area (failed bulkhead gasket, detached fresh-air vent, or clogged A/C evaporator drain) and drips onto the Body Control Module and wiring loom in the passenger footwell. The resulting corrosion and shorts cause wide-ranging, intermittent electrical failures. Owners have reported headlights, brake lights, turn signals, and driver-assist systems all cutting out at speed, plus dead batteries and warning-light storms.
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What does U0140 mean on Alfa Romeo?▼
U0140 stands for "Lost Communication with BCM." U0140 is a network communication code meaning a module has lost communication with the body control module (BCM) over the vehicle's data bus. The BCM oversees many body and convenience functions — lighting, door locks, windows, wipers, anti-theft, and gateway communications — so losing contact with it can cause a wide range of seemingly unrelated electrical problems and warning lights. This is typically a wiring, connector, power/ground, or bus fault, or a failure of the BCM itself. Because the BCM often acts as a communication hub, this code can appear alongside other 'lost communication' codes. On Alfa Romeo specifically, this code is documented across 1 model.
What causes U0140 on Alfa Romeo vehicles?▼
Common causes on Alfa Romeo: Loss of power or ground to the BCM, CAN/data bus wiring damage, short, or open circuit, Corroded, loose, or damaged BCM connectors, Blown fuse feeding the BCM, Failed body control module. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix U0140 on a Alfa Romeo?▼
Repair costs on Alfa Romeo range from $300 to $1,500, depending on the specific model and root cause.
Which Alfa Romeo models have U0140 documented?▼
Au7o has documented U0140 on 1 Alfa Romeo model: Giulia.