OBD Guide

U0038

Vehicle Communication Bus B Performance

U0038 is an OBD-II diagnostic trouble code meaning: Vehicle Communication Bus B Performance. Common causes: open or short circuit in communication bus b, fault in one of the modules connected to the bus. Estimated repair cost: $6–56.

Severity
⚠️ Medium
Can you drive?
Yes, but get it checked soon
Approx. repair cost
$6–56 (est.)

Symptoms

  • Incorrect operation of electronic systems
  • Check Engine Light Illuminates
  • Lost connection with some modules
  • Intermittent dashboard malfunctions

Causes

  • Open or short circuit in communication bus B
  • Fault in one of the modules connected to the bus
  • Poor contact in connectors
  • Interference in the electrical system
  • Wiring harness damage

How to Fix

  1. Check continuity of communication bus B
  2. Inspect connectors for corrosion or damage
  3. Test modules connected to the bus
  4. Check for interference in the electrical system
  5. Replace damaged wires or connectors

Related codes

Error U0038 by Vehicle Brand

FAQ

What does the U0038 code mean?

U0038 is an OBD-II diagnostic trouble code that indicates: Vehicle Communication Bus B Performance

What causes a U0038 error code?

The most common causes of U0038 include: Open or short circuit in communication bus B; Fault in one of the modules connected to the bus; Poor contact in connectors; Interference in the electrical system.

How do I fix a U0038 diagnostic trouble code?

To fix U0038: Check continuity of communication bus B. Inspect connectors for corrosion or damage. Test modules connected to the bus. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0038?

Yes, but get it checked soon

How much does it cost to fix U0038?

The estimated repair cost for U0038 is $6–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat