Semi-Truck Body Control Module (BCM) Failure and Repair | UpFix

Why Are My Lights or Electrical Accessories Acting Up?

When headlights flicker, windows stop working, or random electrical issues appear, the Body Control Module (BCM) is often the hidden culprit. The BCM acts as the truck’s electrical nerve center—it manages everything from lighting and locks to wipers and cabin electronics.

Over time, exposure to moisture, heat, and vibration can damage the BCM’s internal circuits. When this happens, the system begins to send false signals or fails to distribute power correctly.

Common BCM Symptoms

• Headlights, taillights, or marker lights not responding

• Random warning lights appearing on the dash

• Power locks or mirrors stop working

• Electrical accessories intermittently fail

A failing BCM can make diagnosing problems frustrating since it affects multiple systems simultaneously.

Why Repair Instead of Replace

OEM BCM replacements can be expensive and often require complex reprogramming. Used BCMs may not match your truck’s configuration or VIN.

UpFix repairs your original BCM, preserving all factory data. We test and rebuild circuits using upgraded components designed to handle heavy-duty use.

UpFix BCM Repair Process

1. Complete diagnostic scan to isolate board-level faults

2. Replacement of damaged chips, relays, and power transistors

3. Reflow of solder joints and moisture protection

4. Bench-testing of all lighting and accessory outputs

Supported Brands

Freightliner, Kenworth, Peterbilt, Volvo, Mack, International and others.

Get your truck back on the road and keep your costs low.
Send your part to UpFix for professional testing and repair.
We’ll restore it to like-new condition, save you up to 80% compared to buying new, and make it plug-and-play ready when returned.