U0140 on Audi
Lost Communication with BCM
U0140 on Audi vehicles indicates lost communication with bcm. Au7o has documented this code across 1 Audi model — most commonly on S7. 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.
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 Audi by Model
Audi S7(1 issue)
- Rear-Seat Liquid Spill Can Shut Down Gateway Module (Recall 22V861 / 90V2)2020-2022
On certain 2020-2022 S7 vehicles, liquid spilled in the rear seat can reach the gateway control module, shut it down, and suddenly reduce engine power.
Looking for U0140 on a different make?
View U0140 across all makes →Frequently Asked Questions
What does U0140 mean on Audi?▼
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 Audi specifically, this code is documented across 1 model.
What causes U0140 on Audi vehicles?▼
Common causes on Audi: 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 Audi?▼
Repair costs vary widely depending on the root cause and specific Audi model.
Which Audi models have U0140 documented?▼
Au7o has documented U0140 on 1 Audi model: S7.