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U0142 on Mercedes-Benz: Symptoms, Causes & Fix

Lost Communication with Body Control Module B

Official technical diagnostic wire for fault code U0142 specifically affecting Mercedes-Benz vehicles (C-Class, E-Class, S-Class, GLC, GLE).

Sensor Voltage Ref
0.1V – 5.0V Ref
Mercedes-Benz Factory Standard
CAN Bus Speed
500 kbps CAN-FD
ISO 15765-4 Diagnostic Bus
Drivability Status
Drivable (Short Trip)
Medium urgency level
Est. Repair Cost
$120 - $500
Parts & Labor DIY
Model-Specific Diagnostic Wires

Select Your Mercedes-Benz Model for U0142:

7 Models Available

1. Common Symptoms on Mercedes-Benz Vehicles

When Mercedes-Benz Engine Control Modules (ECM) trigger fault code U0142, drivers typically report:

Lighting or power seat glitches on Mercedes-Benz Powertrains
Warning chime on Mercedes-Benz Powertrains

2. Root Causes on Mercedes-Benz Engines

Historical diagnostic claims across Mercedes-Benz engines point to the following failure distribution:

55%
CAN bus communication break (Mercedes-Benz OEM Part)
25%
Blown BCM fuse (Mercedes-Benz OEM Part)
12%
Faulty BCM module (Mercedes-Benz OEM Part)

3. Step-by-Step Fix Protocol for Mercedes-Benz

01
Scan and Record Freeze Frame Telemetry

Connect an OBD-II scan tool and record freeze frame sensor telemetry for code U0142 to note engine RPM, load, and voltage when the fault triggered. on Mercedes-Benz engines.

Required Tool: OBD-II Scanner
02
Inspect Related Wiring Harness & Connectors

Inspect the electrical connector and wiring harness related to U0142 for chafing, corrosion, moisture, or pin push-out. on Mercedes-Benz engines.

Required Tool: Flashlight, Multimeter
03
Test Component Resistance & Voltage Supply

Measure circuit voltage supply (12V B+ or 5V reference) and sensor/actuator resistance according to factory repair manual specifications. on Mercedes-Benz engines.

Required Tool: Digital Multimeter
04
Replace Defective Component

Install a new OEM-grade replacement part, torque fasteners to factory spec, and ensure electrical locking tabs click firmly. on Mercedes-Benz engines.

Required Tool: Hand Tool Socket Set, Torque Wrench
05
Clear Trouble Codes & Complete Drive Cycle

Clear all stored DTCs from vehicle memory and perform an OBD-II drive cycle to confirm the diagnostic monitor resets to 'Ready'. on Mercedes-Benz engines.

Required Tool: OBD-II Scanner
Recommended Parts & Testing Tools

Equipment for Diagnosing Mercedes-Benz (U0142)

Prime Fast Delivery & Verified Fitment
Direct-Fit Replacement Part

Mercedes-Benz OEM Replacement Sensor

4.7 / 5.0 (Verified Fit)

Direct-fit replacement assembly engineered to OEM tolerances for Mercedes-Benz.

$45 – $95 Prime
Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Mercedes-BenzVerified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
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4. Mercedes-Benz U0142 Frequently Asked Questions

What does code U0142 mean on a Mercedes-Benz?

On Mercedes-Benz vehicles, U0142 indicates that the Engine Control Module (ECM) detected lost communication with body control module b. This typically points to CAN bus communication break or Blown BCM fuse.

Can I continue driving my Mercedes-Benz with code U0142?

Yes. Secondary body electronics offline. Because this code carries a Medium severity rating on Mercedes-Benz powertrains, we recommend scanning live data values promptly to prevent secondary damage.

How much does it cost to fix code U0142 on a Mercedes-Benz?

Estimated DIY parts cost ranges from $120 - $500, while professional shop repairs at an authorized Mercedes-Benz dealership or independent specialist typically range from $180 to $380 including diagnostic labor.