OBD Guide

U0242

Lost Communication With Headlamp Control Module B

U0242 is an OBD-II diagnostic trouble code meaning: Lost Communication With Headlamp Control Module B. Common causes: open or short circuit in the wiring to the module, malfunction of the headlight control module. Estimated repair cost: $56–167.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$56–167 (est.)

Symptoms

  • Some headlight functions do not work (for example, cornering lights)
  • Error message on the dashboard
  • Headlights only work in basic mode
  • Adaptive lighting does not function

Causes

  • Open or short circuit in the wiring to the module
  • Malfunction of the headlight control module
  • Connector corrosion
  • Module power problems
  • Software glitches

How to Fix

  1. Check the integrity of wiring and connectors
  2. Test the power supply and ground of the module
  3. Scan the module for additional errors
  4. If necessary, replace the headlight module
  5. Reflash the module if there are updates

Related codes

Error U0242 by Vehicle Brand

FAQ

What does the U0242 code mean?

U0242 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Headlamp Control Module B

What causes a U0242 error code?

The most common causes of U0242 include: Open or short circuit in the wiring to the module; Malfunction of the headlight control module; Connector corrosion; Module power problems.

How do I fix a U0242 diagnostic trouble code?

To fix U0242: Check the integrity of wiring and connectors. Test the power supply and ground of the module. Scan the module for additional errors. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0242?

Limited driving only, diagnose soon

How much does it cost to fix U0242?

The estimated repair cost for U0242 is $56–167. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat