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DTC codes / U05xx · Network communication / U05B3

U05B3Invalid Data Received From Comfort and Convenience Display B

U05B3 is a generic communication fault indicating that a control module received invalid or corrupted data from the comfort and convenience display, which is the screen or interface that manages climate, audio, and vehicle settings. The computer detected that the data stream from this display module failed a validity check, such as a missing message, incorrect checksum, or out-of-range values, so it flagged the signal as unreliable.

SystemNetwork
Code typeGeneric (all makes)
SeverityLow
Fix difficultyIntermediate
AreaNetwork communication

Symptoms you may notice

  • The check engine light or a communication warning light illuminates on the dashboard.
  • The comfort and convenience display may be blank, flicker, or show garbled information.
  • Climate control, audio, or other settings on the display may become unresponsive or behave erratically.
  • Intermittent operation of the display, sometimes working correctly after a restart.
  • Often no symptoms besides the warning light, especially if the fault is intermittent.

Common causes, most likely first

  1. A weak or failing 12-volt battery, or poor battery terminal connections, causing voltage drops that disrupt module communication.
  2. Corroded, loose, or damaged wiring and connectors in the communication network between the display and other modules.
  3. A software glitch or outdated firmware in the comfort and convenience display module.
  4. A failing comfort and convenience display module itself, due to internal electronic faults.
  5. A fault in another module on the same communication bus that corrupts the data stream.
  6. Water intrusion or physical damage to the display unit or its wiring harness.

How to diagnose and fix it

  1. Perform a battery and charging system test, including load testing and checking terminal cleanliness and tightness.
  2. Use a scan tool to read all stored codes and freeze-frame data, then clear codes and test-drive to see if U05B3 returns.
  3. Visually inspect the wiring and connectors at the comfort and convenience display and along the communication bus for corrosion, chafing, or loose pins.
  4. Check for technical service bulletins (TSBs) or software updates for the display module that address communication faults.
  5. Perform a voltage drop test on the power and ground circuits to the display module to rule out resistance issues.
  6. If wiring and power are good, substitute a known-good display module or reflash the existing module with updated software.
  7. After repair, clear codes and verify that the display operates correctly and no communication faults return.

Hidden Causes of Display Communication Faults

  • A marginal battery often causes this code without any display symptoms, because the module drops offline during cranking and logs an invalid data fault.
  • Corrosion inside a connector that looks fine from the outside is a frequent culprit, so always back-probe terminals and check for water tracks.
  • The code can be set by a different module on the same bus sending corrupted data, so do not replace the display until you have checked all nodes.
  • Aftermarket accessories wired into the display circuit, such as dash cams or phone chargers, can introduce electrical noise that corrupts communication.
  • A software reflash often resolves the issue even when no hardware fault is found, because the original firmware may have a known communication bug.

Can I keep driving with U05B3?

The vehicle remains safe to drive because this fault affects comfort and convenience features rather than critical systems, but avoid relying on the display for climate or audio control until it is repaired. If the display is needed for safety functions like rearview camera or defrost, address the fault promptly.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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