U023B: Lost Communication With Image Processing Module B

What it means

A control module has stopped receiving expected messages from image processing module B. The code identifies the communication loss; image-processing functions that rely on the module may be unavailable.

At a glance

• Usually lights the warning light of the system that lost communication
• The engine or gearbox may go into limp mode

How it works

Image processing module B analyzes image data for the vehicle functions assigned to that module. U023B is set when another module stops receiving expected network messages from module B, which is distinct from a loss of communication with image processing module A.

Common causes

Most likely first.

1. Loss of power or ground to the module
2. Open, shorted, or damaged network wiring or connector
3. Failed module

Symptoms

• One or more image-processing or driver-assistance functions may be unavailable
• A warning may appear depending on the vehicle

How to diagnose it

1. Use a scan tool to record freeze-frame data and check for related image-processing, camera, or network codes that may identify a shared fault.
2. Check live data or system status specifically for image processing module B, and note which image-based or driver-assistance features are unavailable.
3. Inspect module B’s connector and accessible network wiring, including any related camera connections identified by vehicle information, for looseness, corrosion, or damage.
4. Check module B’s power and ground against the manufacturer’s wiring information.
5. Test the network wiring to image processing module B for opens or shorts using the manufacturer’s procedure.
6. If wiring and supplies pass, follow the vehicle-specific procedure to determine whether module B has failed.

Common fixes

• Reconnect or repair a loose or corroded connector at image processing module B.
• Repair damaged network wiring to module B.
• Restore module B’s power or ground connection.
• Replace image processing module B if testing confirms it has failed.

Can I keep driving?

Treat driver-assistance functions that depend on image processing module B as unavailable, even if functions using module A still work. Drive cautiously and do not rely on the affected assistance to detect hazards.