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OBD-II trouble code

U0141: Lost Communication with Body Control Module B (BCM B)

A module on the network can no longer hear from a second body control module. Body electrical features tied to that module may stop working and warning lights may appear. Usually a power, ground, wiring, or connector fault at the module.

Quick facts

System
Network
Category
Network Communication
Severity
Medium severity
Drivable
Usually safe to drive short-term
Repair cost range
$100$900
DIY difficulty
Shop recommended

What does U0141 mean?

U0141 is set when another module on the vehicle's communication network stops receiving messages from a second body control module, designated 'B.' Many vehicles distribute body electrical control across more than one module; the 'B' module typically handles a portion of the body functions — lighting, door and access features, convenience electronics, or a specific zone of the vehicle — while a primary BCM handles the rest. When the network loses contact with BCM B, the controller logs U0141 and the features that module manages stop responding to network commands.

The causes are the usual communication-code set. The module may have lost power or ground through a blown fuse, a corroded ground, or a wiring fault. The CAN wiring to the module may be damaged, or its connector corroded or have a backed-out terminal — and because body modules are often tucked behind kick panels, under the dash, or in a door, faults frequently follow interior trim, door, or accessory work that disturbs the harness. Water intrusion is a common culprit for body modules located low in the vehicle or in the doors. The module itself can fail internally, and another module on the bus can disrupt communication for everyone.

The symptoms depend entirely on what BCM B controls on a given vehicle, which varies widely by make and model. You might see specific lighting, door lock, window, mirror, courtesy lighting, or convenience features stop working, intermittent electrical behavior, or interior warning messages. Because the affected functions are usually comfort and convenience rather than propulsion, the car typically still starts and drives, which is why U0141 is generally a medium-severity, driveable fault — but the inoperative features can include safety-relevant lighting, so it's worth diagnosing.

Common causes

  • Blown fuse feeding body control module B
  • Corroded or loose ground for the module
  • Damaged CAN wiring to body control module B
  • Corroded or backed-out terminal at the module connector
  • Water intrusion at a module located low in the vehicle or in a door
  • Harness disturbed during interior trim, door, or accessory work
  • Failed body control module B
  • Another module on the bus disrupting network communication

Symptoms

  • Specific body electrical features (lighting, locks, windows, mirrors) inoperative
  • Intermittent electrical behavior in the affected zone
  • Interior warning messages or chimes
  • Courtesy or convenience features not responding
  • Scan tool can't communicate with body control module B
  • Car still starts and drives normally
  • Symptoms vary widely by make and model

Diagnostic steps

  1. 1.Scan all modules and confirm body control module B is the unreachable one while others respond.
  2. 2.Identify on this specific vehicle which functions BCM B controls and where it is located.
  3. 3.Check the module's power and ground fuses and connections.
  4. 4.Inspect the module connector for corrosion, looseness, backed-out terminals, and signs of water intrusion.
  5. 5.Review any recent interior, door, or accessory work that could have disturbed the harness.
  6. 6.Measure CAN-High and CAN-Low at the module connector and verify continuity to the bus; if power, ground, and wiring are good but the module won't communicate, replace and program it.

Repair cost

$100$900

A blown fuse, corroded ground, or connector repair is the cheapest fix at $100-$300 plus $150-$300 diagnostic time. Drying out and resealing a water-intruded connector or repairing wiring runs $150-$500. Body control module B replacement runs $300-$900 including programming; cost varies with how accessible the module is and whether it must be configured to the vehicle. Always rule out power, ground, water, and wiring before replacing the module.

Estimate your repair

Run the numbers for your vehicle

Open the Repair Cost Estimator with module communication / can bus diagnosis preselected. Adjust labor rate and vehicle category to fit your situation.

DIY vs shop

Leave this one to a qualified shop. It typically involves emissions-critical components, refrigerant handling, or other work that requires manufacturer-grade tooling, training, or certification. DIY attempts often produce a more expensive problem than the original code.

Related codes

Frequently asked questions

What does body control module B do?

It depends on the vehicle. Many cars split body electrical control across more than one module, and the 'B' module handles a portion of the body functions — often a specific group of features like certain lighting, door and access functions, or convenience electronics, or a particular zone of the car. Because the split varies by make and model, the first diagnostic step is identifying what BCM B controls on your specific vehicle.

Can I still drive with U0141?

Usually yes. BCM B typically manages comfort and convenience features rather than the engine or transmission, so the car normally still starts and drives. The catch is that whatever features that module controls may stop working, and that can include safety-relevant items like certain lights. Drive it if you must, but get it diagnosed — and double-check that your exterior lighting still works.

Could water have caused this?

Quite possibly. Body modules are often located low in the vehicle, under the dash, behind kick panels, or in the doors, where water from a leak, a clogged drain, or a car wash can reach them. Water intrusion corrodes connectors and circuit boards and is a common cause of body-module communication faults. Checking the module and its connector for moisture and corrosion is an important early step.

Does a replacement module need programming?

Almost always. A new body control module has to be programmed and configured to your specific vehicle — its options, features, and security data — with a manufacturer-level scan tool before everything works correctly. That's why module replacement is usually a professional job, and why it's worth confirming the module has truly failed before buying one.

AutoLogicTools provides general automotive planning information. Trouble code interpretations, repair cost ranges, and DIY guidance vary by vehicle, model year, location, parts quality, and shop labor rate. Always verify a diagnosis with a scan tool and a qualified automotive professional before approving repairs.