What it means
The reporting module has lost communication with digital audio control module B. It sets this code when expected messages from that module are not received for a specified time.
How it works
Digital Audio Control Module B manages a separate designated part of the vehicle's digital audio system and communicates with other modules over the network. U0194 sets when the reporting module does not receive module B's expected messages within its timeout period.
Common causes
Most likely first.
- Module power or ground fault
- Damaged or corroded network wiring or connectors
- CAN bus short or open circuit
- Digital audio module failure
- Low battery voltage
Symptoms
- Audio functions unavailable or intermittent
- Audio system warning or error message
- Other communication codes
How to diagnose it
- Scan all modules and record freeze-frame data and communication codes to determine whether module B alone has dropped offline or other network nodes are affected.
- Check battery condition and charging voltage, since low voltage can disrupt module B communication.
- Inspect digital audio module B's power, ground, and network connectors for looseness, corrosion, or damage.
- Check the network wiring on module B's branch for opens or shorts using the vehicle wiring diagram.
- With correct power and ground confirmed, test network communication at module B and compare results with the manufacturer's specification.
Common fixes
- Reseat or clean module B's network connector.
- Repair damaged power, ground, or network wiring to digital audio module B.
- Correct a weak battery or charging-system problem.
- Repair a CAN bus fault confirmed on module B's network branch.
- Replace or reprogram digital audio control module B if testing confirms it has failed.
Can I keep driving?
Audio functions assigned to digital audio module B may be intermittent or unavailable, but U0194 alone does not usually affect engine operation or emissions. Driving is generally unaffected unless other codes point to a fault in a vehicle control or safety system.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.