OBD Guide

U0028

Vehicle Communication Bus A

U0028 is an OBD-II diagnostic trouble code meaning: Vehicle Communication Bus A. Common causes: broken or damaged can bus wires, short circuit in can circuit. Estimated repair cost: $6–56.

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

Symptoms

  • Check Engine light comes on
  • Incorrect operation of various vehicle systems
  • Lost connection with some modules
  • Dashboard malfunctions
  • Problems with diagnostics via OBD-II

Causes

  • Broken or damaged CAN bus wires
  • Short circuit in CAN circuit
  • Fault in one of the connected modules
  • Poor contact in bus connectors
  • Problems with module power supply

How to Fix

  1. Check the integrity of the CAN bus wiring
  2. Inspect connectors and contacts for oxidation
  3. Check power supply of all connected modules
  4. Diagnose each connected module separately
  5. If necessary, replace damaged wiring sections

Related codes

Error U0028 by Vehicle Brand

FAQ

What does the U0028 code mean?

U0028 is an OBD-II diagnostic trouble code that indicates: Vehicle Communication Bus A

What causes a U0028 error code?

The most common causes of U0028 include: Broken or damaged CAN bus wires; Short circuit in CAN circuit; Fault in one of the connected modules; Poor contact in bus connectors.

How do I fix a U0028 diagnostic trouble code?

To fix U0028: Check the integrity of the CAN bus wiring. Inspect connectors and contacts for oxidation. Check power supply of all connected modules. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0028?

Yes, but get it checked soon

How much does it cost to fix U0028?

The estimated repair cost for U0028 is $6–56. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat