OBD Guide

U0274

Lost Communication With Lighting Driver Control Module B

U0274 is an OBD-II diagnostic trouble code meaning: Lost Communication With Lighting Driver Control Module B. Common causes: open or short circuit in the can bus, poor contact in the lighting module connectors. Estimated repair cost: $33–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$33–167 (est.)

Symptoms

  • Auxiliary lighting functions not working
  • Error message on the dashboard
  • Incorrect operation of automatic lighting
  • Flashing or unstable headlights

Causes

  • Open or short circuit in the CAN bus
  • Poor contact in the lighting module connectors
  • Lighting control module B fault
  • Module power problems
  • Corroded contacts or damaged wiring

How to Fix

  1. Check power and ground of lighting control module B
  2. Inspect connectors and wiring for damage
  3. Check the integrity of the CAN bus with a multimeter
  4. Scan other modules for related codes
  5. If necessary, replace the faulty module

Related codes

Error U0274 by Vehicle Brand

FAQ

What does the U0274 code mean?

U0274 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Lighting Driver Control Module B

What causes a U0274 error code?

The most common causes of U0274 include: Open or short circuit in the CAN bus; Poor contact in the lighting module connectors; Lighting control module B fault; Module power problems.

How do I fix a U0274 diagnostic trouble code?

To fix U0274: Check power and ground of lighting control module B. Inspect connectors and wiring for damage. Check the integrity of the CAN bus with a multimeter. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0274?

Limited driving only, diagnose soon

How much does it cost to fix U0274?

The estimated repair cost for U0274 is $33–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat